GB2129178A - Display unit - Google Patents

Abstract

A display unit has a display area 2 with three regions 21, 22 and 40 that provide displays of: the nature of an input variable, the value of the input variable, and the units of the input variable displayed. The input variable signal is supplied to the unit via a connector comprising a socket mounted on the unit, and a plug. The plug has pins which mate with the socket. Some of the pins carry the input signal whilst others provide a coding for the plug according to the nature of the input variable. Legends are displayed in two regions 21 and 40 according to the coding, and in the other region 22 according to the input signal. <IMAGE>

Description

SPECIFICATION Display units This invention relates to display units.

The invention is more particularly, but not exclusively, concerned with display units for vehicles, such as, aircraft, ships or submarines.

In many vehicles it is necessary to display simultaneously the value of many different input variables. This is usually achieved by the use of individual display units for each input variable.

Each display unit must indicate the nature of the input variable, may have a unique mode of presentation, and will commonly include a specialised processing unit for deriving a signal from the input variable in a form suitable to drive the display. Because of this, it will be appreciated that each display unit must be different from others of the units. In order for the manufacturer or the user to provide spares, he must have replacements for each of the display units so that if any one fails it can be changed. It will be seen that this entails high expense and that it also leads to an increase in weight and storage space necessary. This can be a particular problem where spares are to be carried on a vehicle.

It is an object of the present invention to enable the above-specified problems to be substantially alleviated.

According to one aspect of the present invention, there is provided a display unit including a display area which is arranged to display the value of an input variable and a legend indicative of the nature of the input variable, a processing unit arranged to drive the display area in response to the input variable, and a connector whereby the display unit is connected to receive a signal representative of the input variable, the connector comprising a first part mounted with the display unit and a second part coupled to receive said signal, wherein the second part of said connector is coded such that it is indicative of the nature of the input variable, and wherein the processing unit is responsive to the coding of the second part of the connector such as to provide display of a legend in the display area in accordance with the coding.

In this way, the same display unit may be used to display the value of different input variables, by connecting it with the appropriately coded second part of a different connector.

The display area may include a region having a matrix array of electrically-energisable elements by which the legend indicative of the nature of the input variable is displayed. The display area may be arranged to display a legend indicative of the units of the input variable and may include a region having a matrix array of electricallyenergisable elements by which the legend indicative of the units of the input variable is displayed. The processing unit may be arranged to control display of the value of the input variable in accordance with the coding of the connector. The parts of the connector may have a plurality of mating pin and socket elements. Some of the elements may be connected to receive the input variable signals, and others of the elements may provide the coding.The second part of the connector may be coded according to which of the said other elements are connected to a voltage source.

A display unit for a submarine in accordance with the present invention, will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of the display unit; Figure 2 is a schematic sectional side elevation of the unit of Figure 1; Figure 3 is a schematic perspective view of a plug for connection with the unit; Figure 4 is a rear view of the plug of Figure 3; and Figure 5 illustrates the use of several display units in a submarine.

With reference first to Figures 1 and 2, the display unit comprises a metal housing 1 having a display area 2 on its front face 3 and two connector sockets 4 and 5 on its rear face 6. The housing 1 contains electronic circuits 10 for suitably processing an input variable to drive the display area 2.

A power source 40 is connected via cable 41 to a plug 42 that is received in the socket 4. The socket 4 is connected via a lead 43 to the electronic circuits 10 within the housing.

The other socket 5 forms part of a connector, the other part of which is provided by a plug 50 which is received within the socket 5. Input variable signals on a cable 51 are supplied to the display unit via the plug 50. The plug 50 is shown in greater detail in Figures 3 and 4 and will be seen to be of the kind having a number of pins 52 mounted parallel to the connector axis in an insulative block 53. Some at least of the pins, namely pins 52A, 52B and 52C are connected with respective individual wires 54, 55 and 56 in the cable 51, these wires carrying the input variable signals. Four other pins 52D, 52E, 52F and 52G are used as coding to identify the nature of the input variable. The coding provided by the pins 52D to 52G differs for cables 51 having input variable signals, from different sources.

Various ways of coding the plug 50 are possible. In the present embodiment, two of the pins 52E and 52F are connected to a fifth pin 52H.

The fifth pin 52H, when mated with the socket 5, is connected to a lead 60 in the unit across which a steady low voltage is applied. Thus, by measuring the voltage on the pins 52D to 52G it is possible to determine that pins 52E and 52F are connected to the voltage line whereas 52D and 52G are not. In this way, a coding 0110 is given. It will be appreciated that by using four pins in this manner sixteen different codings can be provided ~increasing the number of pins increases the variety of different codings that can be given a plug.

Alternatively, the coding could be achieved by the use of resistors of different values connected between pins in the plug.

The leads 60 extend from the socket 5 and connect it with a processing unit 61 within the circuit 10. More particularly, leads 60A, 60B and 60C carry the input variable signal, whilst leads 60D to 60G enable the coding of the plug 50 to be determined. It will be appreciated that many more leads may interconnect the socket 5 with the processing unit 61 so that different input variable signals can be supplied to different parts of the processing unit.

The processing unit 61 includes an encoder 62 that identifies the nature of the input variable from the coding of the plug, as signalled along leads 60D to 60G, and supplies signals representative of the nature of the input variable to a first display drive unit 70, via line 63. The input variable signals on leads 60A, 60B and 60C are suitably processed by the unit 61 and supplied via lines 64 to a second display drive unit 71. In this respect, the processing unit 61 controls the scaling, sampling rate and format of the display from the nature of the input variable, as indicated by the coding of the plug.

The display drive units 70 and 71 supply signals to different display regions 21 and 22 on the display panel 2. The upper display region 21 is formed of a matrix array of electrically-energisable elements 23 (Figure 1) such as light-emitting diodes, whilst the lower region is formed of seven, seven-segment elements 24. The upper, matrix array region 21 is driven to display a legend in the form of letters indicative of the nature of the input variable, for example, 'DEPTH', 'SPEED', 'HEADING', 'LATITUDE', 'LONGITUDE' and so on.

The lower display region 22 is driven to indicate numerical value, namely that of the input variable.

It will be appreciated that both regions could have a matrix array, and that the elements forming the array could be of any of the conventional types.

A third display region 40 is also included on the panel to display a legend indicative of the units of measurement. This is also energised by the drive unit 70 to display a legend such as 'METRES', 'KNOTS', 'DEGREES' and so on.

The display drive units 70 and 71 are of conventional form. The drive unit 70 has stored therein, in a memory 72, signals representative of the energisation pattens for each of the legends which the display unit is capable of displaying. An addresser 73 reads out the stored signals from the appropriate storage locations in the memory 72 in accordance with the signals on line 63 representative of the nature of the input variable.

The other drive unit 71 is suitably arranged to energise selected segments of the elements 24 to display the appropriate number representative of the value of the input variable in accordance with signals on line 64.

One application for such display units is in submarines where, for example, a display panel might be made up of nine such units 101 to 109, as shown in Figure 5. In this application, each display unit is identical with others making up the panel but, because each receives a different input variable signal via a differently coded plug, the legend and the number value displayed by each is different. In this way, fewer spare units need be carried since, if any one unit fails, it does not have to be replaced by a specialised unit dedicated to displaying one function, but can be replaced by the standard display unit which immediately provides the desired display when the coded plug is fitted in its input socket. Because fewer spares need be carried, weight, space, and expense can be saved.

Instead of having a matrix-array display region 21 for displaying the legend, separate display regions may be used for different legends so that, by energising one or other of the separate regions the appropriate legend is made visible. Additional display regions may be provided, such as the region 25 shown on the unit 108, whereby a warning or other indication can be displayed.

Claims (10)

1. A display unit having a display area which is arranged to display the value of an input variable and a legend indicative of the nature of the input variable, a processing unit that is arranged to drive the display area in response to the input variable, and a connector whereby the display unit is connected to receive a signal representative of the input variable, the connector comprising a first part mounted with the display unit and a second part coupled to receive said signal, wherein the second part of said connector is coded such that it is indicative of the nature of the input variable, and wherein the processing unit is responsive to the coding of the second part of the connector such as to provide display of a legend in the display area in accordance with the coding.

2. A display unit according to Claim 1 , wherein the display area includes a region having a matrix array of electrically-energisable elements by which the legend indicative of the nature of the input variable is displayed.

3. A display unit according to Claim 1 or 2, wherein the display area is arranged to display a legend indicative of the units of the input variable.

4. A display unit according to Claim 3, wherein the display area includes a region having a matrix array of electrically-energisable elements by which the legend indicative of the units of the input variable is displayed.

5. A display unit accordance to any one of the preceding claims, wherein the processing unit is arranged to control display of the value of the input variable in accordance with the coding of the connector.

6. A display unit according to any one of the preceding claims, wherein the parts of the connector have a plurality of mating pin and socket elements.

7. A display unit according to Claim 6, wherein some of the elements are connected to receive the input variable signals and wherein others of the elements provide the coding.

8. A display unit according to Claim 7, wherein the second part of the connector is coded according to which of the said other elements are connected to a voltage source.

9. A display unit substantially as hereinbefore described with reference to the accompanying drawings.

10. Any novel feature or combination of features as hereinbefore described.