BACKGROUND OF THE INVENTION TH IS invention relates to an electrical cabie extension reel with a safety switch, More specifically, the invention relates to an electrical cable extension reel having a safety switch thereon that renders the extension reel electrically inoperable unless the cable Is wholly unwound from the reel, It is common knowledge that the inner layers in particular of a wound-up extension cable tend to heat up when connected to a load. In fact, where large currents are pulled through the cable by the loads, the cable can heat up to the point of melting its insulation, causing short circuits and ultimately fires. To prevent the aforementioned dangers, extension cable reel manufactures typically mark their products with a warning instructing users to use the product only after completely unwinding the cable from the reel. Unfortunately, such warnings are simply ignored or wear off the product through use. To better protect users, attempts have been made to mechanically switch the reel off unless the cabie is completely unwound from the reel, Mo t are fairly complicated In operation, making them costly and cumbersome. It is believed that it is for these reasons that such safety cable reels are not readily available in the market today. Accordingly, It Is an object of the present invention to provide an electrical cable extension reel with a safety switch that is simply in operation, as well as cheap and easy to manufacture. SUMMARY OF THE INVENTION

According to the invention there is provided a extension reef for an electrical cable including: a spool having at least a first electrical connector located thereon for electrically connecting the extension reel to a load; a length of cable having a first end extending from the spool and a second electrical connector at a second free end thereof for electrically connecting the extension reel to a power source, the cable being movable onto and off of the spool between respective wound-up and unwound states; an actuator mounted on the spool and movable relative thereto between an operative condition, wherein at feast an end of the actuator lies m close proximity with the spoof, and an inoperative condition, wherein at least the same end of the actuator is distal from the spool, the actuator being retainable in the operative condition by at least a single winding of the cable onto the spool; and a safety switch electrically connected between the cable and the first electrical connector, the safety switch being co-operative with the actuator and operabiy actuated thereby between:

(i) an electrically "on" condition, coinciding with the operative condition of the actuator, wherein electrical continuity between the cable and the first electrical connector in maintained; and

(ii) an electrically "off condition, coinciding with the inoperative condition of the actuator, wherein electrical continuity between the cable and the first electrical connector is broken; such that in the unwound state, the reel is electrically operable, and in the woundup state or partially wound-up state, the reel is rendered electrically Inoperable, Generally, the spool compnses a central drum and first and second flanges each located at opposing ends of the central drum, the spool being rotatabiy mounted on a support and rotatahle thereon about a central axis in a first direction, to wind up the cable into the wound-up state, and in a second direction, to draw the cable from the spool into the unwound state.

Typically, the support is an axle supported on a support frame, the support frame having legs on which the support frame operab y stands and a carrying handle by which the support frame is capable of being operably carried .

Although the first electrical connector may be at least one electrical socket and Ihe second electrical connector may be an electrical plug, it will be appreciated that the reverse may apply. Alternatively, the first and second electrical connectors may be one and the same, i.e. both could be either electrical sockets or electrical plugs.

Preferably, the actuator is a bar having a first end mounted on the spool and a second free end movable radially relative to the spool such that in the operative condition, the second free end of the actuator bar lies at a first radial distance from the central axis of the spool, and in the inoperative condition, the second free end of the actuator bar lies at a second radial distance from the central axis of the spool, the second radial distance being greater than the first radial distance.

More preferably, the actuator bar, with the second free end thereof located at the second radial distance from Ihe central axis of the spool in the inoperative condition, is abutable with the legs and/or the handle of the support frame thereby to prevent the cable from being w und-up state while the reel is electrically operable.

Most preferably, the first end of the actuator bar is hingedly mounted on the spool near the first flange such that the actuator bar is angularly displaceable relative to the central drum of the spool between the operative condition, wherein the actuator bar lies axiaily across an outer surface of the central drum of the spool with the second free end of the actuator bar located near the second flange of the spool, and the inoperative condition, wherein the actuator bar extends radially from the spool such that the second free end of the actuator bar extends beyond a rim of the first flange of the spool. Generally, the actuator bar is a substantially elongate and fiat, and conforms substantiall to the profile of th outer surface of the central drum of the spool.

Typically, the extension reel includes a means for biasing the actuator bar towards the inoperative condition, the biasing means being bias built into the safety switch and/or an independent biasing means operative between the actuator bar and the spool.

Where the biasing means is an independent biasing means, the independent biasing means is preferably a spring.

The safety switch may be a limit switch, more preferably a spring loaded limit switch and most preferably a spring loaded roller arm type limit switch.

Furthermore, the extension reel generally also includes a secondary manual switch located on the spool for switching the extension reel on and/or off operabiy where the safety switch is in the "on" position.

Preferably, the extension reel includes a winding handle on the spool for rotating the spool between the wound-up and unwound states,

BRiEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings in which:

Figure 1 is a perspective view of an electrical cable extension reel with a safety switch in accordance with the present invention, in a wound-up state with the safety switch and an actuator thereof in respective electrically "off' and inoperative conditions; Figure 2 is a perspective view of the extension reel of figure 1 , with the cable being drawn off of a spool thereof thereby moving the extension reel into an unwound state; Figure 3 is a perspective view of the extension reel of figure 2 in the wholly unwound state;

Figure 4 is a perspective view of the extension reel of figure 3 in the unwound state with the safety switch and the actuator thereof in respective electrically "on" and operative conditions;

Figure 5 is a zoomed-in perspective view of the extension reel of figure 4;

Figure 8 is a perspective view of the extension reel of figure 5, with the actuator and the safety switch thereof being returned towards the respective inoperative and electrically "off conditions;

Figure ? is a perspective view of the extension reel of figure 6, with the actuator and the safety switch thereof returned to the respective inoperative and electrically "off conditions and with the cable being wound up onto the spool of the extension reel;

Figure 8 is a perspective view of the extension reel of figure 7 returned to the wound-up state with the cable wholly wound up onto the spool of the extension reel; and

Figure S is a schematic view of the internal circuitry of the extension reei.

DEX t I3 De§¾

An extension reei for an electrical cable according to a preferred embodiment of the invention is designated generally with reference numeral 10 in figure 1 , illustrating the extension reel 10 in a wound-up state. The extension reel 10 comprises a spool 12, a length of cable 14 extending from the spool 12 and a support frame 16 on which the spool 12 is rotatably mounted about a central axis A.

With reference now also to any one of figure 3 to 8, illustrating the extension reef 10 in an unwound state, the extension reel 10 further comprises an actuator 18 mounted on the spool 12, which actuator 18 is co-operative with a safety switch 20 also located on the spoof 12 of the extension reel 10.

The spool 12 is made up of a central drum 22 and first and second flanges 24, 26, each of which being located at an opposite end of the central drum 22 and having a diameter greater than the diameter of the central drum 22 thereby to contain the cabie on the central drum 22 between the first and second flanges 24, 28.

The spool 12 further comprises, preferably on the first flange 24 thereof, one or more first electrical connectors 28 for electrically connecting a load (i.e. an appliance) to the extension reel 10, a manual switch 30 for switching the extension reel 10 on and/or off and a winding handle 32 for winding the spool 12 between the wound-up and unwound states. It will be appreciated that the cabie 14 may be drawn from the spoof 12 into the unwound state by simply pulling the cable 14 directly therefrom without using the winding handle 32.

The cable 14 extends from the spool 12 from a first end 34 thereof and comprises at a second free end thereof a second electrical connector, typically in the form of an electrical plug 38, for electrically connecting the extension reel 10 to a power source 100.

The support frame 16 comprises a pair of legs 38 on which the support frame 16 operabiy can stand and a carrying handle 40 by which the support frame 16 and consequently the entire extension reel 10 can be operabiy carried.

The support frame 16 supports the spool 12 in a cantiievered fashion on a support axle (not shown). Although the spoof 12 has been illustrated as being supported in a cantiievered fashion in the accompanying figures, if will be appreciated that if may for example be supported at both ends. in the preferred illustrated embodiment of the invention, the actuator is in the form of an elongate and fiat actuator bar 18 substantially conforming to the profile of the outer surface of the central drum 22 of the spool 12. The actuator bar 18 has a first end 18A and a second free end 1 SB, with the first end 18A thereof being hingedty mounted to the spool 12 by a hinge 42 at or near the second flange 26 of the spool 12 in this manner, the second free end 18B of the actuator bar 18 is movable, more specifically angularly displaceabie, radially relative to the spool 12 between operative condition and inoperative conditions. In the operative condition, as illustrated most dearly in figures 2 and ?, the actuator bar 18 lies axialiy across the outer surface of the central drum 22 of the spool 12 in close proximity thereto and with the second free end 1 SB of the actuator bar 18 located near the first flange 24 of the spool 12. It will be appreciated that in this condition, the second free end 13B of the actuator bar 18 lies at a first radial distance relative to the central axis A.

In the inoperative condition, as illustrated most clearly in figure 4, the actuator bar is angularly displaced relative to the central drum 22 of the spool 12 such that the second free end 183 of the actuator bar 18 is distal from the central drum 22. It will be appreciated that in this position, the actuator bar 18 is orientated substantially perpendicularly with the central axis A with the second free end 18B thereof lying at a second radial distance relative to the centra! axis A, wherein the second radial distance is greater than the first radial distance, it will be appreciated further that the second radial distance is greater than a radial distance measured between the carrying handle 40 or the iegs 38 of the support frame 16 and the central axis A such that with the actuator bar 18 positioned in the inoperative condition, the spool 12 is prevented from being wound through abutment of the actuator bar 18 with the carrying handle 40 or the legs 38 of the support frame 18.

With reference to figure 9,. the safety switch 20 s connected between the cable 14 and the electncai sockets 28 of the spool 12, more particularly between the cable 14 and the manual switch 30, which in turn is electrically connected to the electrical sockets With reference also to figures 3, 4 and 6, the safety switch 20 is co-operative with the actuator bar 18 and operably actuated thereby between an e!ectncal!y "on" condition, coinciding with the operative condition of the actuator bar 18, and an electrically "off condition, coinciding with the inoperative condition of the actuator bar 18.

In use, with the extension reel 10 in the wound-up state (i.e. with the cable 14 wound up onto the spooi 12) as illustrated in figure 1 , the aotuaior bar 18 is retainable in the inoperative condition, consequentially retaining the safety switch 20 in the electrically "off condition thereby rendering the extension reef 10 is electrically inoperative regardless of It being connected to the power source 100 and the on / off position of the manual switch 30.

In this manner, an electrical current is Incapable of flowing through the cable 14. As such, the wound up cable 14 will never; (i) overheat; (is) melt its insulation and cause a short circuit; and/or (iii) cause a fire.

For the extension 10 to become electrically operable, the cable 14 must be drawn from the spool 12 as illustrated in figure 2 Once the cable 14 is wholly unwound from the spool 12 as illustrated in figure 3, the actuator bar 18 is free to move from the inoperative condition to the operative condition, consequently causing the safety switch to move from the electrically "off' condition to the electrically "on" condition respectively.

If will be appreciated that just a single winding of the cable 14 on the spool 12 is sufficient to retain the actuator bar 18 in the inoperative condition. It will be appreciated further that biasing means, within the safety switch 20 or independent therefrom, will bias the free actuator bar 18 into operative condition and that a user is required to force the actuator bar 18 into the inoperative condition against the bias of the biasing means where he / she wishes to wind in the cable 14.

With the extension reel 10 in the unwound state as illustrated in figure 4, and with the electrical plug 36 of the cable 14 plugged into the power source 100, the manual switch 30 may be used to further switch power to the electrical sockets 28 on the spool 12 on off. With the manual switch on, and with an electrical load 200 plugged Into the electrical socket 28. the electrical load is electrically connected and powered by the power source 100 as illustrated in figure 5. in this operating condition, the actuator bar 13 extends radially beyond the carrying handle 40 (and the legs 38) of the support frame 16. Accordingly, the spool 12 is prevented from rotating fully about the centra! axis A by abutment of the actuator bar 18 with the carrying handle 40 (or the legs 38) of the support frame 16, thereby preventing the cable from being wound up and consequently preventing the extension reel 10 from being used in the wound-up state,

As soon as the actuator bar 18 Is moved by the user from the operative condition to the in-operative condition as illustrated in figure 8, the actuator bar 18 co-operates with the safety switch 20, causing the safety switch 20 to move to the electrically "off condition thereby breaking current flow,

With the actualor bar 18 returned fully to the inoperative condition as illustrated in figure 7, the cable 14 is capable of being wound up onto the spool 12 until the extension reel 10 is returned to its fu!iy wound-up state as illustrated in figure 8. Although the invention has been described above with reference to preferred embodiments, it witl be appreciated that many modifications or variations of the invention are possible without departing from the spirit or scope of the invention,

For example, instead of he actuator bar 18 being angularly dispiaceable relative to the spool 12, it may be linearly movable in a radial direction relative thereto.