FLEXIBLE COVER FOR SCREEN OF AN ELECTRONIC DEVICE

Abstract: A folding cover (22) for an electronic device such as a palm-top computer (20) having a display screen (21) is disclosed. It can lie flat against the screen (21) or be folded to a position outside the contour of the computer (20) when the cover is flat against the screen. The screen has a track (33) running along each side in which one end of the folding cover (22) is engaged. The cover construction may be applied to analogous devices with display screens such as mobile telephone units.

Description: FLEXIBLE COVER FOR SCREEN OF AN ELECTRONIC DEVICE This invention relates to electronic devices incorporating a sensitive screen, and particularly to such devices including a casing and means fitted to the casing for protecting the screen against damage. In recent years, increasing use has been made in electronic devices, of display screens which enable the user of the device to determine, by viewing the screen, what the device is doing. The classic cathode ray tube is robust, but large, and increasingly, especially in portable electronic devices such as palm-top computers, mobile telephones and hand-held games machines, use is made of small flat LCD screens. Such screens are relatively fragile, so care has to be taken, e.g. by mounting them recessed from the front of a casing, to reduce the risk of damage. They may also be mounted behind a rigid glass or transparent plastics window. A particular problem arises in the case of screens which are overlaid by a so-called "touch screen", which acts to enable the user of the device to interact with it by pressing selectively on part of the touch screen, which part being identifiable by means of suitable markings, indicia or icons being displayed on the LCD screen behind the touch screen. The touch screen itself consists of a pair of spaced apart sheets, at least one of which is relatively flexible, which may be brought selectively into contact by pressing on a desired area of the touch screen. If this has only one flexible sheet, it is positioned outermost. A conductive layer on the facing spaced apart faces of the sheets, usually of indium tin oxide, and associated electronic circuitry, enables the position of the selected contact to be determined and appropriate input signals to be generated to control the device. The selective pressing to form the contact may be achieved with a fingertip or, e.g. a separate stylus. This mode of controlling the electronic device is advantageous in that conventional control buttons can be largely or wholly dispensed with. It is known to protect such LCD screens, and if present touch screens thereover, with a lid or cover, generally hinged to one side of the screen (as disclosed, for example, in US-A-5555157 and EP-A-0865184 ) , or clippable in place. An alternative approach is to make the casing of the device in which the LCD screen is mounted in two parts, one slidable with respect to the other, so that by sliding one part of the casing, the screen may be revealed or hidden - see for example O97/03511. EP-A- 0846999 discloses an alternative approach with a rolling shutter formed of slats on a flexible backing. Alternatively, a relatively rigid slip cover may be provided for the entire device. These approaches are not always satisfactory: hinged covers tend to snap off, clip-on covers and slip covers can become lost, and slidable casing portions can be easily broken so they do not then function satisfactorily. According to the present invention, there is provided in a casing for an electronic device with a display screen, especially with a touch screen overlaying the display screen, a captive flexible cover member, the cover member being hinged at one edge to the casing and having at its opposite edge means engaging in a pair of spaced parallel tracks extending either side of the screen, whereby the flexible cover member may be flexed from a substantially flat configuration in which the cover member covers the screen, and with the track engaging means remote from the hinged edge, to a flexed configuration with the track engaging means engaging the tracks adjacent the hinged edge, and with the cover member folded or arched in a loop extending outwardly from the casing. Preferably the flexible cover member is made of a material which is relatively flexible or bendy about one direction and which is relatively stiff or rigid against flexing in a direction perpendicular thereto. Such a cover member may be constructed in the fashion of a tambour door or rolltop desk cover, comprising a set of at least several rigid rod or slat members on or within a flexible sheet, e.g. of rubbery sheet material. Alternatively the flexible cover member may be formed of a flexible backing sheet having a relatively small number of, most preferably two, relatively rigid plates separated by small gaps and attached to the backing sheet. Preferably the tracks and engagement means are formed to enable the cover to be selectively held in open or closed position, i.e. revealing or covering the screen respectively. For example, the tracks may incorporate clipping formations in which the engagement means may be temporarily lodged. It is also convenient to arrange for the engagement means to actuate, when moved to the position in which the screen is revealed, some type of switch mechanism acting to 'switch on' the electronic device. Alternatively, one end of the cover member may be mounted hingedly about a suitable axis, and that end may cooperate with means located near that axis which can detect whether the position of the end of the cover member corresponds to the screen covering or the screen revealing position. The invention is illustrated, by way of example, with reference to the accompanying drawings, in which Figure 1 is a perspective view of a palm-top computer with a casing according to the invention, with a display screen revealed; Figure 2 is a view as Figure 1, but with the cover closed; Figure 3 is a perspective view of a mobile telephone unit with a casing according to the present invention; Figure 4 is a perspective view of an alternative form of palm-top computer with a casing according to the invention; Figures 5a, b and c are diagrammatic sections through the computer of Figure 4 showing the cover member in three portions; Figure 6 is a perspective view of the metal components of the cover member shown in Figures 4 and 5; and Figures 7 a and b are diagrammatic details of the mounting of the end of the cover member shown in Figures 4 to 6 with respect to other parts of the casing of the palm-top computer. Referring first to Figures 1 and 2 , a palm-top computer has a generally rectangular parallelipipedic casing 1 and a display screen 2. Four actuation buttons 9 are shown, but control is mainly effected via a touch screen over the display screen 2. A flexible cover sheet 3 is fitted at two opposite ends with rigid bars 4 and 5. Bar 4 is hinged at one edge of the casing 1 about a hinge line 6. Bar 5 slides in a pair of facing tracks 7 set to either side of screen 2. Bar 5 bears a raised area 8 which may be engaged by a thumbnail to open or close the cover. The tracks 7 have formations near their ends adjacent buttons 9 which allow bar 5 to be held captive against that end of the track, and which are sufficiently resilient to enable the bar 5 to be sprung out of position and moved along the tracks to open the cover and reveal the screen 2. Similar clipping formations may act to latch bar 5 in the position shown in Figure 1. As shown in Figure 3, the invention may be used in casings for other electronic equipment, in this case a mobile telephone 9. This is of conventional design, save for the protection of the screen 12 which is effected by a cover 10 which is shown in Figure 3 in the open position. The mobile telephone 9 is provided with an earpiece 14 and an aerial 16. The majority of the telephone operation is controlled via screen 12. Cover 10 is attached to and moves relative to the body of the mobile telephone 9 in the same fashion as described in connection with Figures 1 and 2. The cover 10 is, however, attached to the body of the mobile telephone 9 adjacent the end of the mobile telephone 9 remote from the earpiece 14 and aerial 16. This results in the cover 10 resembling a mouthpiece for the telephone when in the open position. Movement of cover 10 may activate one or more switches in channels 7 to cause specific operations of the telephone. Referring now to Figures 4 to 7 , these show an alternative cover construction for a palm-top computer, denoted 20 in Figure 4, which is configured to act as an on/off switching device for the computer. A generally rectangular display screen which is overlaid by a touch screen if desired denoted 21 may be covered when the computer 20 is not in use by a folding cover 22. Folding cover 22 consists of a flexible sheet of material 24 attached to two metal components 25 and 26, the shaping of which is clearly evident from Figure 6. Together, components 24, 25 and 26 make up the cover 22. Component 26 consists of a generally flat plate which is folded over at one side edge 30 around a rod 31 which protrudes from either end of fold 30. The protruding ends of rod 31 are dimensioned to engage in tracks 33 which are located to either side of screen 21. The other component 25 consists of a generally flat plate shaped and bent at one edge to provide a channel 36 and a set of arched lugs 37. The function of the channel 36 is to receive a fixed axle 40 extending from one side to the other of the casing of palm-top computer 20 and which can be seen in Figures 7a and 7b. Also is shown in those Figures are diagrammatically the shape of a recess internally of the external casing of palm-top computer 20 adjacent two of its corners. Arched lugs 37 lodge within these recesses and because they form a generally cylindrical surface, they allow smooth rotation of component 25 generally around the axle 40. Each recess contains two moulded beads 41, 42 and the component is associating with spring means (diagrammatically indicated at 44) which act to urge axle 40 towards the bottom of slot 36. This provides a latching action selectively holding the component 25 in one of two radial positions around the axle 40, with the top of the slot 36 engaging on pip 41 when the cover member is closed (as shown in Figure 7a) and with bead 42 when the cover 22 is open to reveal the screen 21, as shown in Figure 7b. The flexible cover member 22, which is adhered to components 25 and 26 using a suitable adhesive, is omitted from Figures 7a and 7b for the sake of clarity. As shown in Figure 4, the end of the flexible member 22 is deformed to constitute a lip 46 adjacent edge portion 30 of component 26 in order more easily to be able to move the cover from a closed screen covering position shown in Figure 5a and 7a in the direction of the arrow identified as 50 in Figure 5b and 5c to the open screen revealing position shown in Figure 4 and Figure 5c. As the lip 46 is initially pushed in the direction of arrow 50, the ends of rod 31 slide along tracks 33 and the cover member 22 arches up as shown in Figure 5b and then folds on to itself as shown most clearly in Figure 5c. It will be appreciated that because of the engagement of the open edge of slot 36 with pip 42 internally of the casing of the palm-top computer 20, the folded cover 22 is held away from the screen area. As the cover is opened, the outer bottom end of slot 36, denoted 55 in Figure 7b, may be made to actuate an appropriate switch member, for example the actuation arm of a microswitch, to turn the palm-top computer 20 on. In order to close the cover, all that is required is to push the outer folded edge up gently in the direction of arrow 60 as shown in Figure 4. This moves component 25 so that the opening of slot 36 disengages from bead 42 and the natural resilience of flexible member 24 then tries to make that member flat again, thus moving the cover 22 from the position shown in 5C to that shown in 5a. The ends of rod 31 being freely slidable in tracks 33, this takes place simply and smoothly and the cover latches into a flat position covering screen 21 as the opening of slot 36 comes to engage on bead 41 under the biasing action of spring 44.

Claims: CLAIMS 1. A casing for an electronic device with a display screen, and a captive flexible cover member, the cover member being hinged at one edge to the casing and having at its opposite edge means engaging in a pair of spaced parallel tracks extending either side of the screen, whereby the flexible cover member may be flexed from a substantially flat configuration in which the cover member covers the screen and with the track engaging means remote from the hinged edge to a flexed configuration with the track engaging means engaging the tracks adjacent the hinged edge, and with the cover member folded or arched in a loop extending outwardly from the casing. 2. A casing according to Claim 1 in which a touch screen overlies the display screen. 3. A casing according to Claim 1 or 2 in which the flexible cover member is constructed from a material flexible in a first direction and stiff in a second direction substantially perpendicular to the first direction. 4. A casing according to Claim 3 in which the flexible cover member is comprised of rigid rod or slat members on or within a flexible sheet. 5. A casing according to Claim 1 or 2 wherein the cover member is formed of a flexible backing sheet attached to two relatively rigid plates separated from one another. 6. A casing according to any one of Claims 1 to 5 in which the tracks and cover member include cooperating means enabling the cover member to be selectively held in its open or closed position. 7. A casing according to any one of Claims 1 to 6 and including means cooperating with part of the cover member to switch the electronic device on and off as the cover is moved from its flat configuration to its flexed configuration and vice versa respectively. 8. A palm-top computer having a casing according to any one of Claims 1 to 7. 9. A mobile telephone handset having a casing according to any one of Claims 1 to 7

Inventors: RIDDIFORD MARTIN PHILIP, RIDDIFORD, MARTIN, PHILIP
Applicants: RIDDIFORD MARTIN PHILIP, THEREFORE LIMITED, RIDDIFORD, MARTIN, PHILIP
Application year: 1999
Main classification: G06F1
IPC codes: F16C11, G06F1, G06F3, G06F15, H04M1, H05K5