WO2001095763A1

WO2001095763A1 - Screen display apparatus

Info

Publication number: WO2001095763A1
Application number: PCT/GB2001/002525
Authority: WO
Inventors: Simon James Hopkins; Carl Woolley; Paul Alan Glover
Original assignee: Tnci Uk Ltd.
Priority date: 2000-06-10
Filing date: 2001-06-08
Publication date: 2001-12-20
Also published as: GB0014124D0; AU2001264060A1

Abstract

A screen display apparatus (10) comprises a screen assembly (18), which is selectively movable between a stored position in which the screen assembly (18) is substantially contained within the screen display apparatus (10), and an operative position in which the screen assembly (18) is substantially extended from the screen display apparatus (10) for viewing. A cam arrangement (50, 52) forces the screen assembly (18) to tilt about a pivotal mounting (78, Fig. 5) during the movement between the stored and operative positions. The screen assembly (18) is mounted in a cradle (66) which is moved by cross arms (46, 48, Fig. 4) and lead screws (22, 24) driven by an electric motor (30). Alternatively, the cradle (66) is moved by gas struts, or by hand.

Description

TITLE: Screen Display Apparatus

The present invention relates to a screen display apparatus, and more particularly to a screen display apparatus for mounting a screen assembly.

In recent years screen technology, together with information technology, has advanced significantly. Consequently there now exists a requirement for a screen display apparatus which can be fitted easily to desks, tables and other working and leisure surfaces for use in, for example, offices, Internet cafes, trains, ships, aircraft and the home.

According to the present invention there is provided a screen display apparatus comprising a screen assembly, the screen assembly being selectively movable between a stored position in which the screen assembly is substantially contained within the screen display apparatus, and an operative position in which the screen assembly is substantially extended from the screen display apparatus for viewing, characterised in that a cam arrangement forces the screen assembly to tilt about a pivotal mounting during the movement between the stored and operative positions.

Preferably, moving means is provided for moving the screen assembly between the stored and operative positions.

The moving means may comprise an electric motor which drives a pair of lead screws, the lead screws being in threaded engagement with a pair of respective cross arms for driving the cross arms along their respective lead screws. The screen assembly is preferably resiliently mounted to the cross arms.

Alternatively, the moving means may comprise a pair of gas struts, each of the gas struts having a cylinder and a piston rod, the piston rod being capable of reciprocating movement in and out of the cylinder. The screen assembly is preferably resiliently mounted to the piston rods.

In a further alternative arrangement, the moving means may be a handle, which can be gripped by hand, enabling manual lifting of the screen assembly to the operative position.

It is preferable that the screen assembly is pivotally mounted in a cradle, which cradle is resiliently suspended from mountings on the cross arms or piston rods by means of springs. A pair of stops may be provided on the lower ends of the cradle beneath the screen assembly, which engage the upper casing of the screen display apparatus for limiting the upward movement of die cradle, and hence the screen assembly, out of the screen display apparatus when the lead screws are driving the cross arms.

Preferably, a cam is rigidly attached to each of the cross-arms, the cams engaging respective cam followers provided at each end of the screen assembly. The cross arms and cams are preferably capable of upward movement against the action of the springs, past the position in which the stops limit upward movement of the cradle, the screen assembly and cam followers. Preferably, the action of the cams on the cam followers forces the screen assembly to tilt about its pivotal mounting in the cradle.

Each screen display apparatus may contain one or more screen assemblies, and preferably each cradle mounts two screen assemblies positioned back to back, enabling viewing of the screen assemblies from opposite sides of the screen display apparatus.

A seal may be provided between an upper portion of the screen assembly and a lip of the screen display apparatus, for providing a splash resistant seal between the screen assembly and lip when the screen assembly is in the stored position.

The invention will now be described further, by way of example, with reference to the accompanying drawings in which: Figure 1 shows a perspective view of a screen display apparatus, with a screen assembly in the stored position;

Figure 2 is a perspective view of the screen display apparatus of Figure 1, with the screen assembly in the extended position for viewing;

Figure 3 is a perspective view of the screen display apparatus of Figures 1 and 2 with the screen assembly in an extended and tilted position for viewing;

Figure 4 is an underside perspective view of the screen display apparatus of Figures 1 to 3 showing the driving arrangement;

Figure 5 is a part perspective view of the screen display apparatus of Figures 1 to 4 showing the mounting of the screen assembly;

Figure 6 A is an end view of the cam arrangement with the screen assembly in the extended position;

Figure 6B is an end view of the cam arrangement with the screen assembly in the extended and tilted position;

Figure 6C is an end view of the cam arrangement with the screen assembly in an extended and manually tilted position;

Figure 7 is a schematic diagram showing the relative movement between one of the cam tracks and a respective cam follower; and

Figure 8 is a circuit diagram showing the connections between the electrical components of the screen display apparatus as shown in Figures 1 to 5. Referring firstly to Figure 1, a screen display apparatus is indicated generally at 10. The screen display apparatus 10 consists of abase 12 and an upper casing 14 which are rigidly held together in spaced relation by a central support member 16. A screen assembly 18 is shown in a stored position, that is, contained between the base 12 and upper casing 14. When the screen display apparatus 10 is installed in a work surface or table (not shown), an open topped container (not shown) surrounds the base 12 and closes on to the underside of the upper casing 14, thereby containing and protecting the stored screen assembly and driving assembly, which is described further below. The screen display apparatus 10 is fitted into an aperture in the working surface and is supported by a lip 20 around the periphery of the upper casing 14.

The underside of the lip 20 makes a watertight seal with the working surface, thus preventing liquid from passing through the aperture in the working surface. A seal (not shown) is also provided between the underside of an upper trim portion 96 of the screen assembly 18, and the lip 20, which seals when the screen assembly is in the stored position. The seal can be attached to either the lip 20 or the upper trim portion 96, and is made from a soft material, for example rubber, to protect a persons' fingers, should their fingers be trapped between the lip 20 and upper trim portion 96 in the movement of the screen assembly 18 from the operative to stored positions.

The seal is at least splash resistant, and generally prevents liquids, such as spilt drinks and cleaning fluids used during cleaiiing of the apparatus and working surface, from entering the screen display apparatus 10. The seal may be watertight, depending on its material of manufacture.

Referring also to Figures 2 to 4, a pair of lead screws 22, 24 of the same thread pitch also extend between, and are rotatably mounted to the base 12 and upper casing 14. As can best be seen from Figure 4, the lead screws 22, 24 extend through the base 12 and are provided with respective pulleys 26, 28 on the underside of the base 12. A 12 volt DC electric motor 30 having a gear box 32 is mounted to the base 12, positioned adjacent to the central support member 16 and between the base 12 and upper casing 14. An output shaft 34 from the gear box 32 also passes through the base 12 and is fitted with a drive wheel 36.

A first stepped timing belt 38 provides drive from the drive wheel 36, which is powered by the motor 30, to the pulley 26 for driving the lead screw 22. A second stepped timing belt 40^' connects the pulley 26 to the pulley 28 for providing drive to the lead screw 24. The pulleys 26 and 28 are of equal diameter, and are provided with recesses which correspond to the steps in the belt 38, 40. Consequently the lead screws 22, 24 are driven at the same rate.

Corresponding recesses for the belt 38 are also provided in the drive wheel 36. A pair of adjustable tensioners 42 maintain tension in the belt 38, and two pairs of adjustable tensioners 44 guide and tension the belt 40.

A pair of cross arms 46, 48 incorporating power nuts are in threaded engagement with the respective lead screws 22, 24. The cross arms 46, 48 are at the same perpendicular distance from the base 12 at a given time and move at the same rate along their respective lead screws 22, 24 when the lead screws are driven by the timing belts 38, 40 as previously explained.

A pair of cam plates 50, 52 are rigidly mounted to the. respective cross arms 46, 48. The cam plates 50, 52 extend parallel with the lead screws 22, 24 and are positioned between the lead screws with inner faces 49, 51 facing one another. In an upper portion 54, 56 of each cam plate are two apertures 58 (see Figure 5), the side walls of which form cam tracks 60. The apertures 58 are mirror images about the centre line of the screen display apparatus 10, and are substantially triangular. The shape of the apertures 58, and hence the cam tracks 60 is described further below.

Each cam plate 50, 52 has a respective dovetail slot 62, 64 formed in the inner surface 49,

51 of the cam plate facing the other cam plate. A cradle generally indicated at 66, and best seen in Figures 4 and 5, comprises two mounting plates 68, 70, which are connected in spaced relation by a central back plate 69 and a base plate 71. Dovetails 72, 74 are formed on the outside surfaces of the mounting plates 68, 70 and are engaged for vertical sliding movement in the respective dovetail slots 62, 64 of the cam plates 50, 52. Hence, the cradle 66 is capable of sliding movement relative to the cam plates 50, 52 and cross arms 46, 48. Furthermore, as can be seen from Figures 6A, 6B and 6C, the cradle 66 is resiliently mounted to the cam plates 50, 52 by means of springs 76. Each cam plate 50, 52 mounts a pair of springs 76 on either side of the dovetail slides.

Referring in particular to Figure 5, the screen assembly 18 is pivotally mounted from its upper edge to the cradle 66 about pivots 78. The pivots 78 are rotatably mounted in the mounting plates 68, 70, and allow the screen assembly 18 to tilt in the cradle 66. Cam followers 80 (see also Figures 6A, 6B and 6C) extend from the sides of the screen assembly 18, through arcuate slots 82 cut in the mounting plates 68, 70 of the cradle, and into the apertures 58, whereupon they contact the cam tracks 60.

Referring in particular to Figure 7, each cam track is formed with a slotted portion 82 at its upper end, which is a relatively snug fit for the respective cam follower 80. As can be seen from the Figure 6A, when the cam follower 80 is located in this slotted position 82, position A, the screen assembly 18 is in a closed position, substantially parallel with and adjacent to the central back plate 69 of the cradle 66.

Upward movement of the cam plates 50, 52 relative to the cradle 66, screen assembly 18 and hence the cam follower 80, causes the cam follower to travel along the surface 84 of the cam track 60 to position B. Consequently, the follower 80 is forced to move in an arc away from the central plate 69, which causes the screen assembly to tilt about the pivot 78 through an angle X (Figure 6B) to an improved viewing position. The extent of horizontal movement of the cam follower 80 is indicated at Y in Figure 7.

The screen assembly 18 can now be manually tilted further to any position between the position shown in Figure 6B and the limiting position shown in Figure 6C. During this manual movement, the cam follower 80 moves along the lower surface 86 of the cam track 60, until the cam track 60 prevents further movement at position D. The screen assembly 18 is held in the desired position by means of a ratchet (not shown).

From the fully tilted position, position D, downward movement of the cam plates 50, 52 relative to the cam follower 80 causes the follower to engage and move along a "capturing" surface 88 of the cam track 60 back to the slotted portion 82, position A. This causes the screen assembly 18 to move back from the tilted position (Figure 6C) to the closed position (Figure 6A).

If the screen assembly 18 is tilted manually to a position between the positions shown in Figures 6B and 6C, then the cam follower 80 stops in its path along the lower camming surface 86, as shown in Figure 7, for example at position C. On downward movement of the cam plates 50, 52, the follower 80 remains stationary and the screen assembly 18 remains at the same angle of tilt until the cam track surface 88 captures the follower 80 at position E. Then as previously described, the follower 80 returns to position A. It should be understood that the arrows in Figure 7 merely represent the relative movement between the cam track 60 and the follower 80. In practice, the cam follower 80 simply moves in an arc about the pivot 78 of the screen assembly 18, under the action of the cam track 60 and the possible manual movement.

Referring back to Figure 1, anti- vibration blocks 90 (only one of which is shown) are fitted to the underside of the base plate 71 and fit into U-shaped guides 92 fitted to the screen display apparatus base 12, when the screen assembly 18 is in the stored position. A pair of stops (not shown) are also provided on the base plate 71 of the cradle 66 which engage the upper casing 14 of the screen display apparatus 10 for limiting the upward movement of the cradle, and hence the screen assembly 18 out of the screen display apparatus 10 when the lead screws 22, 24 are driving the cross arms 46, 48 upwards. As can best be seen from Figure 5, brackets 94 are fitted to the mounting plates 68, 70 of the cradle 66, for receiving the upper trim portion 96 (Figures 1 to 4). A truncated conical housing 98 protrudes through the trim portion 96, and houses a circular push button switch 100 for an operator to control the up and down movement of the screen assembly 18. The switch 100 is of significantly less diameter than the housing 98 and a lamp 108 (see Figure 8) illuminates the space between the switch 100 and the housing wall 98.

The casing 14, as viewed to the left of the trim portion 96 in Figures 1 to 4, houses a card reader, a headphone socket and a Universal Serial Bus port, (USB port). When the screen assembly 18 is in the stored position, a cover prevents access to the card reader slot, the socket and the USB port However, when the screen assembly 18 moves towards the operative position, an arm 102 attached to the cross arm 46 engages a pin 104 which actuates opening of the cover on upward movement of the arm 102. A torsion spring (not shown) returns the cover to its closed position when the screen 18 returns to the stored position.

The circuitry for controlling the motor 30 and the lamp 108 is generally indicated at 106 in Figure 8. The circuit 106 comprises a micro-controller 116, a 12 volt DC power supply, an oscillator 118, three MOSFET power switches 110, 112 and 114, and a set of signal switches 120. One of the signal switches 120 is the on/off switch 100, and the other signal switches 120 act as sensors winch determine whether the screen assembly 18 is in the stored or operative position. The output from the signal switches 120 is fed back to the micro- controller 116 and software determmes the starting position of the screen assembly 18 and accordingly turns the power switches 110, 112, 114 on or off as required.

The switch 110 controls the lamp 108 which is driven with a pulse modulated wave form. This wave form is programmed to give a dynamic brightness and dimming function. The switch 112 controls the drive of the motor in one direction with a positive voltage, and the switch 114 controls the drive of the motor in the other direction with a negative voltage. The oscillator 118 determines the clock speed of the micro controller 116 and thus the speed of programme execution. In the operation of the screen display apparatus from the stored position, a viewer presses the on/off switch 100 in the trim portion 96. The micro-controller 116 turns on the power switch 110 and the lamp 108 begins to pulse, thereby illuminating the space around the switch 100 with each pulse. The micro-controller 116 also recognises from the signal switches 120 that the screen assembly 18 is in the stored position and operates one of the motor switches 112, 114 to drive the screen assembly 18 towards the operative position.

As the lead screws 22, 24 rotate, the cross arms 46, 48 move upwards to the position in which the cradle 66 and hence the screen assembly are prevented from further movement by the stops on the base plate 71 of the cradle 66 engaging the underside of the upper casing 14. This position is shown in Figures 2 and 6A, and the cam follower 80 is located in the slot 82 of the cam track 60, which corresponds to position A in Figure 7.

Continued driving of the lead screws 22, 24 causes the cross arms 46, 48 and the rigidly attached cam plates 50, 52 to continue their upward movement against the action of the springs 76. The dovetails 72, 74 formed on the mounting plate 68, 72 of the cradle 66 slide in their respective dovetail slots 62, 64 in the cam plates 50, 52. Consequently, the cam tracks 60 move upwards relative to the screen assembly 18 and the cam followers 80. Each follower 80 is consequently moved in an arc, through the horizontal distance Y, by the action of the camming surface 84 to the position B shown in Figure 7. The screen assembly therefore tilts about the pivot 78 to the corresponding position shown in Figures 3, 4, 5 and 6B.

Furthermore, during the continued upward movement of the cross arms 46, 48, the arm 102 engages the pin 104 which opens the cover over the card reader slot, headphone socket and the USB port.

At the limit of travel, one of the signal switches 120 provides feedback to the micro- controller which turns off the motor 30. The lamp 108 also stops pulsing. The viewer may now manually tilt the screen assembly 18 further to any position between the limiting positions shown in Figures 6B and 6C. The screen assembly 18 is held in the selected position by means of a ratchet as previously described. During this manual movement, each cam follower 80 moves between the positions B-C-D, shown in Figure 7, along the camming surface 86.

When the viewer wishes to return the screen assembly 18 to the stored position, he or she again operates the push button switch 100. Retraction of the screen assembly 18 is the reverse of its deployment. The lamp 108 pulses and the cross arms 46, 48 are driven downwards in known manner. The cam plates 50, 52 move downwards relative to the cam followers 80 and the camming surfaces 88 capture the followers, thereby tilting the screen assembly 18 back to its position adjacent and parallel with the central back plate 69 of the cradle 66, before the cradle 66 retracts into the screen display apparatus 10. The ratchet is self releasing. The arm 102 releases the pin 104 and the card reader slot cover returns by means of the torsion spring.

As the cradle 66 reaches the bottom of its travel, the anti-vibration blocks 90 engage the U- shaped guides 92. Finally, at the limit of downward movement, one of the signal switches 120 triggers the micro-controller 116 to turn off the motor 30, and the lamp 108 stops pulsing.

hi a further embodiment of the invention (not shown) the screen assembly moving means is provided by a pair of gas struts. The gas struts each have a cylinder attached to the base 12 and a piston attached to the cross arms 46, 48. The arrangement of the cam plates 50, 52 and the support of the cradle 66 is similar to that of the first described embodiment. The most significant difference is the manual returning of the screen assembly 18 to the stored position from the operative position by pressing downwards on the trim portion 96.

hi a yet further embodiment of the invention (not shown), the screen assembly moving means ^■ is simply provided by a handle fitted to the upper trim portion 96 of the screen assembly 18. The handle is gripped by hand, and the screen assembly manually lifted from the stored to the operative position. A latch automatically engages which holds the screen assembly in the operative position. The latch must be released before lowing the screen assembly 18 back to the stored position.

The screen display apparatus 10 has been developed primarily for use in passenger trains. However, as previously mentioned, it is also suitable for use in other applications. When fitted in the table of a train, the screen display apparatus allows the screen assembly to be stored in a protected position under the table. When deployed into the operative position, it is envisaged that the screen assembly will be linked to a server at the front of the coach in which the screen display apparatus is fitted, as part of a local area network (LAN). The screen assembly will contain a fully interactive touch screen which will display safety information, general passenger notices and a wide selection of films on demand.

Furthermore, the passenger will be able to make reservations, as well as booking and paying for tickets by using the card reader. Thus, the screen display apparatus 10 will provide the passenger with a relaxed and entertaining journey.

Claims

1. A screen display apparatus (10) comprising a screen assembly (18), the screen assembly (18) being selectively movable between a stored position in which the screen assembly (18) is substantially contained within the screen display apparatus (10), and an operative position in which the screen assembly (18) is substantially extended from the screen display apparatus (10) for viewing, characterised in that a cam arrangement (50,52) forces the screen assembly (18) to tilt about a pivotal mounting (78) during the movement between the stored and Operative positions.

2. A screen display apparatus according to claim 1 characterised in that moving means (30) is provided for moving the screen assembly (18) between the stored and operative positions.

3. A screen display apparatus according to claim 2 characterised in that the moving means comprises an electric motor (30) which drives a pair of lead screws (22,24), the lead screws (22,24) being in threaded engagement with a pair of respective cross amis (46,48) for driving the cross arms (46,48) along their respective lead screws (22,24).

4. A screen display apparatus according to claim 3 characterised in that the screen assembly (18) is resiliently mounted to the cross arms (46,48).

5. A screen display apparatus according to claim 3 or 4 characterised in that the screen assembly (18) is pivotally mounted in a cradle (66), the cradle (66) being resiliently suspended from mountings on the cross arms (46,48) by means of springs (76).

6. A screen display apparatus according to claim 5 characterised in that a pair of stops are provided on the lower ends of the cradle (66) beneath the screen assembly (18), which engage the upper casing (14) of the screen display apparatus for limiting the movement of the cradle (66), and hence the screen assembly (18), out of the screen display apparatus (10).

7. A screen display apparatus according to any one of claims 3 to 6 characterised in that a cam (60) is rigidly attached to each of the cross-arms (46,48), the cams (60) engaging respective cam followers (80) provided at each end of the screen assembly (18).

8. A screen display apparatus according to claim 7 characterised in that the cross arms (46,48) and cams (60) are capable of movement against the action of the springs (76) past the position in which the stops limit movement of the cradle (66), the screen assembly (18) and cam followers (80).

9. A screen display apparatus according to claim 7 or 8 characterised in that the action of the cams (60) on the cam followers (80) forces the screen assembly (18) to tilt about its pivotal mounting (78) in the cradle (66).

10. A screen display apparatus according to claim 5, or any of claims 6 to 9 when appendant to claim 5, characterised in that each cradle (66) mounts two screen assemblies (18) positioned back to back, enabling viewing of the screen assemblies (18) from opposite sides of the screen display apparatus (10).

11. A screen display apparatus according to claim 2 characterised in that the moving means comprises a pair of gas struts, each of the gas struts having a cylinder and a piston rod, the piston rod being capable of reciprocating movement in and out of the cylinder.

12. A screen display apparatus according to claim 11 characterised in that the screen assembly is resiliently mounted to the piston rods.

13. A screen display apparatus according to claim 12 or 13 characterised in that the screen assembly is pivotally mounted in a cradle, the cradle being resiliently suspended by means of springs.

14. A screen display apparatus according to any preceding claim characterised in that a seal is provided between an upper portion (96) of the screen assembly (18) and a lip (20) of the screen display apparatus, for providing a splash resistant seal between the screen assembly (18) and lip (20) when the screen assembly (18) is in the stored position.