The invention relates to a device of the kind indicated in the preamble of claim 1 for temporarily anchoring a computer unit to a base surface .

Computer unit here means an independent computer device (e . g . a laptop computer, a handheld computer or a mobile telephone) or a part thereof (e . g . an accessory such as a printer, a games console or an optical reader/printer) , which is in signal communication with other parts of the computer device, whereby the computer device comprises a processor unit, a keyboard and a power supply for each unit (as well as conventional memory functions and software, operating system and programmeware) . Such a computer unit may need to be anchored to a nearby obj ect for various reasons , particularly if the computer unit is light and readily portable . If the computer unit when in use rests on a base surface which is horizontal but which is slippery and/or vibrates , or if the base surface is slippery and slopes, it may happen that the computer unit tends to slide or move on the base surface, particularly during work using the computer unit (e . g . keyboard work) . In other situations it may be desirable to temporarily mount the computer device, e . g . the keyboard control console or a visual display screen which forms part of the computer device, on a very inclined, e . g . vertical , surface or on a work surface which is generally horizontal but turned downwards, if the operator' s working position renders this advantageous . In yet other situations it is desirable to be able to protect the computer unit from being stolen, by anchoring it to a base surface, e . g . a table or some other object which cannot be moved at all or only with difficulty.

An object of the invention is therefore to indicate a device which makes it possible to anchor a computer unit temporarily to a base surface easily, conveniently and safely by using equipment which belongs to the computer device .

This obj ect is achieved by the invention .

The invention is defined in the attached independent claim.

Embodiments of the invention are indicated in the attached dependent claims .

The invention entails fitting a suction pad to the computer unit in such a way that the opening edge of the suction pad substantially contacts the base when the computer unit rests on the base surface . The computer unit has further to be provided with a vacuum pump which may be powered by the computer unit' s power supply . The power supply may take the form of a separate mains unit for the computer unit, possibly in combination with an electric storage battery chargeable thereby. Alternatively, the power supply may take the form of a supply of current via a cable from another part of the computer device, e . g . via a USB cable .

The pump is with advantage controlled by a pressure sensor which detects the pressure difference between the inside of the suction pad and the surrounding atmosphere . The sensor may be settable at an upper and a lower limit pressure, e . g . via the computer device' s basic functions , in order to steer the pump to maintaining a pressure in the suction pad between those values . The suction pad is further provided with a pipeline extending between the inside of the suction pad and the surroundings of the suction pad, whereby the pipeline contains a valve device which is controllable via the keyboard and the processor unit and a code registered in the

computer unit, to enable the suction pad to assume atmospheric pressure .

If a thief tries to steal the computer unit in question and breaks its connections to the mains supply or to other computer units, the negative pressure will persist in the suction pad, rendering the unit very difficult to steal . In cases where the computer unit comprises an electric storage battery, the latter can power the pump under the guidance of the sensor device for a relatively long time and thereby compensate for any air leakage to the suction pad.

The pressure in the suction pad can easily be raised to atmospheric pressure by first connecting the unit in question, where applicable, to other parts of the computer unit, followed by inputting the relevant code for this pressurisation of the suction pad into the computer unit via the latter' s keyboard.

The invention is described below in the form of an example with reference to the attached drawing .

Fig . 1 depicts a laptop computer provided with an anchoring device, whereby the laptop computer is connected to an accessory which is also provided with an anchoring device. Fig . 1 depicts a laptop computer 2 which, via a support surface 10, stands on a smooth planar base surface 1. The computer 2 is shown comprising a fixed but pivotable visual display screen 8 , a keyboard 7 , a chargeable battery 15 and a processor unit 14. The computer 2 can charge the battery 15 via a mains connection which may also power the computer directly. The drawing shows on the underside of the computer 2 a suction pad 16, the free circumferential edge of which is in sealing contact with the base surface 1. A pump 4 and a check valve 5 are connected in series to the inside of the

suction pad 16. A pipeline 11 extends between the inside of the suction pad and the surrounding atmosphere and contains a controllable valve device 12. The pump 4 is provided with power from the battery 15 or the mains unit of the computer 2. The pump 4 can be controlled via the processor unit 14. A pressure sensor 6 is connected to the processor unit 14 and detects the pressure difference between the atmosphere and the inside of the suction pad . The computer unit 2 can be used to set the respective pressure limits at which the pressure sensor will switch off and activate the pump 4.

An operator can use the keyboard to activate the pump via the processor unit 14 so that the pump is provided with power from the power supply (batteries or mains unit) of the computer 2, whereby the air in the suction pad 16 is evacuated and a check valve in the pump device prevents any backflow of air to the inside of the suction pad 16 after the pump 4 has stopped. When the pressure in the suction pad 16 as detected by the sensor 6 falls below a predetermined value, the supply of current to the pump 4 is disconnected by the processor unit 14. If the pressure in the suction pad 16 increases , e . g . because of air leakage due to lack of seal with respect to the base surface 1, this situation is detected by the pressure sensor 6 which, at a predetermined pressure level, starts the pump 4 via the processor unit 14. An alarm device 3 is provided to emit an alarm if the pump cannot hold the pressure in the suction pad below a set upper limit value .

The area of contact of the suction pad 16 with the base surface 1 is large enough to provide stable fastening of the computer unit 2 to the base 1. As the valve device 12 can only be opened by the processor unit 14 via a programme loop which can only be activated via a code put into the processor unit 14 via the keyboard 7 , it is difficult for an

unauthorized person to eliminate the negative pressure in the suction pad by tampering with the valve device 12.

With advantage, as depicted in Fig . 1 , the suction pad 16 is of no great height and is situated in the middle region of the underside of the computer 2 so that it is difficult from outside to tamper with the rubber elastic wall of the suction pad 16 by inserting a tool between the base surface 1 and the underside 10 of the computer 2.

The embodiment referred to above is of course only one example . In another embodiment, the sensor 6 may be connected directly to the pump 4 in order to switch the latter on and off respectively in response to pressure exceeding or falling below corresponding preselected pressure limits . In the embodiment illustrated it is possible for the sensor 6, if it has an output signal representing the detected pressure level in the pad 16, to be used for enabling the processor unit 14 to act upon the pump 4 at pressure limits which are freely chosen and may for example be inputted, via the keyboard 7 , into the processor unit 14 or a memory connected to the latter or into programmeware which controls computer functions .

The drawing shows the suction pad 16 having a bottom sealingly connected to the circumferential rubber elastic wall and constituted by the housing wall of the computer unit 2 or of the accessory 17. The wall of the suction pad is suitably dimensioned so as to be in sealing contact with the base surface 1 when the computer unit 2 rests on the base surface .

As previously mentioned, the suction pad 16 may be used to provide theft protection for the computer unit to which it is fitted. The suction pad 16 may also be used for temporarily

holding the computer unit 2 firmly on a base in order to prevent the computer unit 2 from sliding off a sloping base . The suction pad may of course also be used for holding the computer unit 2 in position on a vertical surface or a turned-down surface .

If the sensor detects that the suction pad 16 is at a pressure which exceeds a preset limit value, it is possible to use the pressure sensor 6 for ensuring that an alarm 3 is triggered (theft alarm) . Such an alarm may of course be acoustic but it may also be passed on, via the processor unit 14 , to other computers in a local area network (LAN) . It may also be seen in Fig . 1 that the computer device 2 comprises a laptop computer connected by a communication cable 9 to an accessory 17 , e . g . a printer or the like . The accessory 17 may likewise comprise items 3 to 14 and 16 as well as its basic accessory devices . The accessory 17 may be regarded as forming part of a computer device which comprises the laptop computer 2 and the accessory 17. The cable 9 is depicted as a physical communication cable which may also carry driving power to the accessory' s pump drive . As an alternative, it is of course also possible for the accessory 17 to have a mains unit of its own and possibly also chargeable batteries which can be charged via the mains unit or via the cable 9. In cases where the accessory 17 has a power supply of its own, the cable 9 may be replaced by a wireless connection for signal transmission between the parts of the computer device .

The drawing shows signal and control lines 13 for connecting power and signal lines to their respective components .