Patent Application
20080003887
This application claims priority of German application No. 10 2006 029 927.2 filed Jun. 29, 2006, which is incorporated by reference herein in its entirety.
The invention relates to an angled plug.
AC power plugs such as angled plugs are used in the home and in many industrial applications.
Power plugs are often pulled out of the socket by the cable, possibly damaging both the cable and the plug. Angled plugs generally have an anti-kink sleeve to protect the cable from bending. However, a high pulling force applied to the cable may nevertheless result in the cable being broken off before the anti-kink sleeve, or even in the anti-kink sleeve being strained, causing the cable to break in the region of the anti-kink sleeve.
In addition to interrupting the power supply for a device connected to the power plug, and necessitating a repair, cable breakage also poses a hazard to people due to the open live wires.
An object of the invention is to specify an angled plug which offers increased safety and reliability when pulling force is applied to a connected power cable.
This object is achieved by an angled plug as claimed in an independent claim.
The angled plug has a device which converts a pull applied to a power cable connected to the angled plug in such a way as to cause the angled plug to be forced out of a socket.
The angled plug can be a plug of any national or international standard, such as a connector known as a non-heating appliance socket and which is used, for example, to supply computers with power.
The angled plug has at least two contact pins which are used to establish electrical contact, e.g. in a socket outlet. Alternatively the angled plug has at least two contact rings which are used to receive contact pins of a plug-in apparatus. An example of this alternative is a so-called non-heating appliance plug which is used, for example, for PCs. The contact pins or contact rings are parallel and define by their respective axes a plane which will hereinafter be referred to as the contact pin plane, irrespective of whether it is formed by the contact rings or contact pins.
The plug-in apparatus for the angled plug will hereinafter be referred to as a socket, the term socket also being intended to include the plug-in apparatus which is generally located on the power supply of a PC, i.e. a non-heating appliance plug.
The anti-kink sleeve, i.e. the start of the power cable connected to the angled plug outside a housing of the angled plug, does not leave the housing in a straight line running contrary to the insertion direction of the angled plug, i.e. the direction of the contact pins of the angled plug, for example. Positively formulated, this means that the anti-kink sleeve makes an angle, e.g. 90°, with the insertion direction of the angled plug. Angles other than 90° are also possible.
Depending on the pulling direction, a pulling force applied to the power cable of the angled plug causes the angled plug to be withdrawn from the socket. Due to the fact that the power cable does not leave the housing of the angled plug in a straight line, the pull applied to the power cable tends to result in the angled plug being jammed in the socket, preventing it from being successfully pulled out of the socket by the power cable.
According to the invention, the pull applied to the power cable via the device additionally causes the angled plug to be forced out of the socket, thereby advantageously preventing the cable from being broken off and therefore preventing the angled plug from being damaged. The safety of the angled plug is therefore increased.
In an advantageous embodiment of the invention, the device is implemented as a lever. The lever is embodied such that when the power cable is pulled a force is generated which assists withdrawal of the angled plug. The lever is of angled design. Alternatively the lever can be of bent design.
It is expedient here to dispose a bearing axle, about which the lever is rotatable, in the housing of the angled plug in the region of the contact pin plane. It is further advantageous to dispose the bearing axle close to an end face of the angled plug on the opposite side from the socket.
It is also expedient to dispose the bearing axle centrally with respect to the housing in the area between the axes of the contact pins or contact rings, in the region of the contact pin plane close to the angled plug's end face on the opposite side from the socket.
This arrangement ensures that conversion of the pull takes place in such a way that the angled plug does not jam, or jams as little as possible, on being withdrawn.
Alternatively it is possible for the device to be implemented as a pair of levers, it being advisable to dispose the levers of the lever pair symmetrically in such a way that the plane of symmetry which would project one lever onto the other corresponds to the plane of symmetry which—in the case of two contact pins—would project one contact pin onto the other. That can mean, for example, that the bearing axle of one of the levers is disposed in the contact pin plane on the right-hand side of a right-hand contact pin close to the angled plug's end face on the opposite side from the socket. Correspondingly, in this example the bearing axle of the other lever is disposed in the contact pin plane on the left-hand side of a left-hand contact pin close to the angled plug's end face on the opposite side from the socket. Alternatively it is also possible to dispose the levers asymmetrically.
Advantageously the lever is embodied in such a way that a first, essentially straight lever arm extends from the bearing axle of the lever into the anti-kink sleeve, while a second, angular lever arm essentially extends as far as the plug head end face in the insertion direction. The plug head end face is defined as the surface of the angled plug from which the contact pins protrude or through which the contact rings extend into the housing.
It is advantageous in this case if the second, angular lever aim essentially ends at the plug head end face, which means that the angled plug essentially has the external shape of angled plugs known from the prior art, but that even a small force applied to the power cable, i.e. a slight pull, causes the angled plug to be forced out of the socket.
In an advantageous embodiment of the invention, the second, angular lever arm is rounded off where it ends at the plug bead end face, thereby preventing mechanical abrasion or destruction of the socket and of the lever arm of the angled plug when the latter is forced out by the device.
In a further advantageous embodiment of the invention, the second, angular lever arm has a wheel where it ends at the plug head end face.
This advantageously means that better conversion of the force acting on the anti-kink sleeve to force the angled plug out of the socket is achieved, as the wheel minimizes the friction of the end of the second, angular lever arm on the socket.
The angled plug is preferably implemented as a grounded Schuko-type plug.
Further details and advantages of the invention will be explained with reference to the accompanying drawings, in which:
The bearing axle L around which the lever H is pivotally mounted is disposed in the plane of the contact pins S in the plug housing C close to the opposite side of the plug housing C to the contact pins. The lever H can be caused to rotate by the anti-kink sleeve K being pulled in the opposite direction to the insertion direction E of the angled plug. If such a force is exerted, the lever H rotates about the bearing axle L. The result of such a rotation is sketched in
In the embodiment of the inventive angled plug shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2006 029 927.2 | Jun 2006 | DE | national |
