DE8633957U1 - Device for reducing the leakage current - Google Patents

Description

* 1 device for reducing the leakage current

The invention relates to a device for reducing the leakage current of mains-powered electrical devices, with an isolating transformer which can be connected to the power grid on the primary side via a mains connection cable and has a connection on the secondary side for connecting an electrical consumer.

The device according to the invention is intended in particular for the field of medical barley, although it can also be advantageous in other areas where a reduction in the leakage current of mains-powered electrical devices is important.

According to safety standards, the leakage current of medical devices must not exceed 500 μα.

In the area of medical devices in particular, other commercially available electrical devices could also be used with advantage if their leakage current was not too high. It is known that the decoupling of an electrical device from the mains can be achieved by means of a built-in isolating transformer, so that there is no galvanically conductive connection between the power grid and the electrical device. However, such measures have largely not been taken for commercially available electrical devices that are not designed for the medical field . 25

The invention solves the problem of creating a device designed in the manner mentioned above, which enables the reduction of the leakage current of commercially available electrical devices without having to modify or retrofit them.

30

This is achieved according to the invention in that the device is designed as a separate adapter device in which the mains connection cable is attached and the isolating transformer is housed, the secondary connection of which is designed as a socket.

35

··■ ·· IiIlIIi

Due to its training as a separate adapter device, in which in addition

the isolating transistor also has a connected to its secondary side socket and which has its own power cable, can be connected to the device according to the invention. Any mains-powered electrical appliance be connected to the power grid while at the same time being galvanically isolated from the grid by plugging the power plug of the adapter device into a power socket and the power plug of the electrical device into the socket of the adapter device.

Preferred catfish Is on the base plate of the adapter device, on which the

Isolating transformer and the socket are supported, in front of the socket a cable clamping device is formed with which the cable of the electrical appliance, after its power plug is inserted into the socket of the adapter device, fixed to the base plate of the adapter device This prevents the plug of the electrical appliance from e.g. when cleaning or tidying up, it is pulled out of the adapter socket and then later mistakenly plugged into a mains socket. In addition, the cable clamp device provides strain relief for the power plug of the adapter device plugged into the socket

electrical appliance.

Although the adapter device according to the invention is designed, for example, It may be that the isolating transformer is housed in a device housing, on the outside of which the socket with its plug openings is arranged, it is preferred for the above reasons to enclose the isolating transformer and the socket within a common device housing, from which the mains connection cable of the isolating transformer is led out on one side and the mains cable of the electrical device can be inserted on the other side. For additional safety To prevent unauthorised access to the plug of the connected electrical device inserted into the socket of the adapter device, a special lock can be provided for the housing which can only be opened with a special tool.

Furthermore, an overload protection device can be used for the isolating transformer as an over

Voltage protection of the primary side of the isolation transformer must be provided.

The invention is explained below with reference to two embodiments, which can be seen in the drawing in perspective representation, where the device housing of the adapter device shown is shown partially broken away.

The adapter device shown in Fig. 1 of the drawing for reducing the leakage current of mains-powered electrical devices contains an isolating transformer 3 in a device housing 6 designed as a rectangular box,

and a socket 2 connected to the secondary side of the isolating transformer 3 via a cable 10, to which an electrical device can be connected via its power cable 11 and power plug 1. The isolating transformer 3 and the socket 2 are mounted on the legs of a common, U-shaped bracket 4, which is fixed with its U-web on the base plate 5 of the adapter device.

The power cable 9 of the isolating transformer 3 is secured to the base plate 5 with strain relief by means of a clamping device β. For the power cable 11 of the electrical device 1, there is also a Cable clamping device 7 for strain-relieved fixing of the power cable 11 on the base plate 5. An overload fuse in a fuse holder 12 is provided as overvoltage protection for the isolating transformer 3.

The embodiment of Fig. 2 largely corresponds to that of Fig.

1. However, according to Fig. 2, the holder 4 for the isolating transformer 3 and the socket 2 has been omitted. Instead, these are attached directly to the base plate 5. For this purpose, the socket 2 is designed as a surface-mounted socket. The cable 10 is led from the isolating transformer under the base plate 5 and connected to the socket 2 on its underside.

Claims (3)

EXPECTATIONS 1. Device for reducing the leakage current of mains-fed electrical devices, with an isolating transformer which can be connected to the power grid on the primary side via a mains connection cable and has a connection on the secondary side for connecting an electrical consumer, characterized by the design as a separate adapter device in which the mains connection cable (S) is fastened and the isolating transformer (3) is arranged, the secondary side connection of which is designed as a socket (2). 2. Device according to claim 1, characterized in that a cable clamping device (7) is formed on the base plate (5) of the adapter device, on which the isolating transformer (3) and the socket (2) are supported and in front of the socket (2). 3. Device according to claim 1 or 2, characterized in that the isolating transformer (3) and the socket (2) are enclosed in a common housing (6).