GB1568287A - Calculating apparatus - Google Patents

Description

(54) iMPROVEMENTS IN OR RELATING TO CALCULATING APPARATUS (7;1) We, ROLLS-ROYCE LIMITED, a Brat'tis Company of 65 Buckingham Gate, London, SWIE 6AT, do hereby declare Ithe invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to calculating apparatus and more particularly to calculating apparatus which is adapted to convert a numerical value to another functionally related value, such as an imperial measurement into metric measurement or vice versa.

According to the present invention calculating apparatus comprises switching means for entering numerical value into the apparatus, indicating means for indicating the value entered, means for converting the numerical value to a functionally related value ånd means for indicating the functionally related value, said apparatus being adapted such that in operation the values indicated by said means for indicating the value entered and means for indicating the functionally related value are displayed 'simulta- neously.

The switching means may comprise a series of marked switches which are adapted to be set to the value to be converted.

Alternatively the switching means may comprise a series of marked keys or pushbuttons which are connected to a suitable visual display such as an L.E.D. display.

The means for converting the numerical value to a functionally related value prefer ably comprises a calculating circuit, the value and the function being fed to the calculating circuit sequentially by means of an oscillator, a counter and a decoding circuit.

Alternatively the numerical value may be fed to the calculating circuit manually, and the function fed to the calculating circuit sequentially by means of an oscillator, a counter and a decoding circuit.

Preferably the means for indicating the functionally related value comprises an L.E.D. display.

Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a diagrammatic representation of the circuit of one embodiment of the calculating apparatus according ;to the present invention and Figure 2 is a diagramatic representation of the circuit of an alternative embodiment of the invention.

The embodiment shown in Figure 1 consists basically or a series Of edge switches S1 to S7 which are of the rotary ;type and are marked with the figures 0 to 9. The figure to be converted, (in this case an imperial measurement of length to its metric equivalent) is entered on the edge switches in inches, and this value is then clearly visible on the switches S1 to S7. Teach of the switches S1 to S7 has internal connections whereby when the switch is supplied with an electrical pulse, the output from the switch represents the value set on the switch in binary code form. Thus each switch has four output lines representing 1,2, 4 and 8 and the pulse is transmitted along one or more of these lines depending on the value set on the switch.

The switches S1 to S7 are connected between a decoder 10 and a calculating intergrated circuit 12 of well-known type. The decoder 10 is adapted to produce a series of pulses sequentially along outputs marked, OBD, 051, OS2, etc. and is clocked by an oscillator 14 and a counter 16. The calculating circuit 12 is also clocked by an oscillator which is connected to a light emitting diode (L.E.D.) display 20. An additional feature is a display blank circuit 22 which switches off the display 20 after preset period of time, in this case 20 seconds.

As mentioned previously, the first output of the decoder 10 is marked OBD, which is connected to the display bank circuit 22, and this circuit is made operative by the first pulse from the decoder 10 after switch 24 is pressed to start the oscillator 14. The next three outputs 051, 082 and 083 are then energised in turn and the values set on the switches 91, 52 and S3 are fed to the calculating circuit 12 in binary code form.

The output ODP represents a decimal point and this output is connected directly to the calculating circuit 12 via an OR gate 26. The outputs Ops4, OS5, 056 and OS7 are connected to the switches S4 to S7, and the values set on these switches are thus sequentially fed to the calculating circuit 12.

The output F is connected to a switch 28 which can be set in one of two positions.

In the position shown, the output F is connected to a multiplying connection in the calculating circuit 12, whilst in its other position the output F is connected to a dividing connection in the calculating circuit 12.

The calculating apparatus can thus be made to convert imperial measurements to metric measurements or vice versa by setting the switch 28 to the multiply or dividing connection respectively. The function for converting imperial measurements to metric measurements is 25.4, and- the following outputs d the decoder 1Q are thus connected to feed the figures (in binary form) 2, 5, decimal point and the figure 4 directly to the calculating circuit 1S The final output E sends a pulse to an "equals" connection on the circuit 12, which causes the calculating circuit to carry out the instructions fed to it from the other outputs d the decoder to. The oscillator 14 is switched off by the counter 16 after the pulse from the output E so that the decoder 10 emits no more pulses until the button 24 is pressed again.

The result of the calculation is fed to the LED. display 20.

Thus the figure to be converted in inches is displayed on the edge switches S1 to 57 and its metric equivalent is shown on the L.ED. display 20. The two displays are particularly useful for checking if an error has been made in entering the figure to be converted.

The display blank circuit 22 switches off the display 26 after the period of 2Q seconds, and another figure can be set on the switches SI to S7 and converted to its metric equivalent Figure 2 shows an alternative arrange ment in which pushtbuttons marked BO to B9 and BDP as used in a conventional pocket calculator replace the edge switches Sl to S7 in Figure 1. These enable a figure to be converted more rapidly entered into the apparatus and in order that the entry can be checked a second L.E.D. display 30 is provided to display the figure entered on the push-buttons. In this case, the value to be converted is entered manually directly to the calculating circuit 12 before the button 24 is pressed to start the oscillator d4. As before the output OBD is then connected to the blank display circuit 22 followed sequentially by the outputs F, 2, 5, ( > DP, 4 and 1, and the metric equivalent is displayed on the display 20.

Various modifications may be made to the circuit without departing from the scope of the invention. Thus, for example, means may be provided for moving the position of the decimal point using a series of gates when a change is made from imperial to metric conversion to metric to imperial conversion by means of the switch 28. This has been found useful because of the large factor difference between inches and millimeters.

The apparatus is suitable- for many conversions of this nature. Thus the outputs 2, 5, DP and 4 shown could be replaced by different figures to convert, for example, pounds to kilos, or means for changing the conversion factor could be provided by suitably inserting switches between these outputs and the- calculating circuit 12.

WHAT WE CLAIM IS: - 1 Calculating apparatus comprising switching means for entering a numerical value into the apparatus, indicating means for indicating the value entered, means for converting the numerical value to affunc- tionally related value and means for indicating the functionally related value, said apparatus being adapted such that in operation, the values indicated by said means for indicating the value entered and means for indicating the functionally related value are displayed simultaneously.

2. Calculating apparatus as claimed in claim 1 in which the switching means comprises a series of marked switches which are adapted to- be set to the value to be converted.

3. Calculating apparatus as claimed in claim 1 in which the switching means comprises a series of marked keys or pushbuttons which are connected to a suitable visual display such as an LE+D. display.

4. Calculating apparatus as claimed in claim 1 or 2 in which the means for converting the numerical value to a functionally related value comprises a calculating circuit, the numerical value and the function being fed to the calculating circuit sequentially by means of an uscillator, a counter and a decoding circuit 5. Calculating apparatus as claimed in claim 3 in which the numerical value is fed to the calculating circuit manually, and the function fed to the calculating circuit seq-uen- tially by means of an oscillator, a counter and a decoding circuit, 6. Calculating apparatus as claimed in any preceding claim in which the means for indicating the functionally related value comprises an L.E.D. display.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

1. **WARNING** start of CLMS field may overlap end of DESC **.

   The output ODP represents a decimal point and this output is connected directly to the calculating circuit 12 via an OR gate 26. The outputs Ops4, OS5, 056 and OS7 are connected to the switches S4 to S7, and the values set on these switches are thus sequentially fed to the calculating circuit 12.

   The output F is connected to a switch 28 which can be set in one of two positions.

   In the position shown, the output F is connected to a multiplying connection in the calculating circuit 12, whilst in its other position the output F is connected to a dividing connection in the calculating circuit 12.

   The calculating apparatus can thus be made to convert imperial measurements to metric measurements or vice versa by setting the switch 28 to the multiply or dividing connection respectively. The function for converting imperial measurements to metric measurements is 25.4, and- the following outputs d the decoder 1Q are thus connected to feed the figures (in binary form) 2, 5, decimal point and the figure 4 directly to the calculating circuit 1S The final output E sends a pulse to an "equals" connection on the circuit 12, which causes the calculating circuit to carry out the instructions fed to it from the other outputs d the decoder to. The oscillator 14 is switched off by the counter 16 after the pulse from the output E so that the decoder 10 emits no more pulses until the button 24 is pressed again.

   The result of the calculation is fed to the LED. display 20.

   Thus the figure to be converted in inches is displayed on the edge switches S1 to 57 and its metric equivalent is shown on the L.ED. display 20. The two displays are particularly useful for checking if an error has been made in entering the figure to be converted.

   The display blank circuit 22 switches off the display 26 after the period of 2Q seconds, and another figure can be set on the switches SI to S7 and converted to its metric equivalent Figure 2 shows an alternative arrange ment in which pushtbuttons marked BO to B9 and BDP as used in a conventional pocket calculator replace the edge switches Sl to S7 in Figure 1. These enable a figure to be converted more rapidly entered into the apparatus and in order that the entry can be checked a second L.E.D. display 30 is provided to display the figure entered on the push-buttons. In this case, the value to be converted is entered manually directly to the calculating circuit 12 before the button 24 is pressed to start the oscillator d4. As before the output OBD is then connected to the blank display circuit 22 followed sequentially by the outputs F, 2, 5, ( > DP, 4 and 1, and the metric equivalent is displayed on the display 20.

   Various modifications may be made to the circuit without departing from the scope of the invention. Thus, for example, means may be provided for moving the position of the decimal point using a series of gates when a change is made from imperial to metric conversion to metric to imperial conversion by means of the switch 28. This has been found useful because of the large factor difference between inches and millimeters.

   The apparatus is suitable- for many conversions of this nature. Thus the outputs 2, 5, DP and 4 shown could be replaced by different figures to convert, for example, pounds to kilos, or means for changing the conversion factor could be provided by suitably inserting switches between these outputs and the- calculating circuit 12.

   WHAT WE CLAIM IS: - 1 Calculating apparatus comprising switching means for entering a numerical value into the apparatus, indicating means for indicating the value entered, means for converting the numerical value to affunc- tionally related value and means for indicating the functionally related value, said apparatus being adapted such that in operation, the values indicated by said means for indicating the value entered and means for indicating the functionally related value are displayed simultaneously.
2. 2. Calculating apparatus as claimed in claim 1 in which the switching means comprises a series of marked switches which are adapted to- be set to the value to be converted.
3. 3. Calculating apparatus as claimed in claim 1 in which the switching means comprises a series of marked keys or pushbuttons which are connected to a suitable visual display such as an LE+D. display.
4. 4. Calculating apparatus as claimed in claim 1 or 2 in which the means for converting the numerical value to a functionally related value comprises a calculating circuit, the numerical value and the function being fed to the calculating circuit sequentially by means of an uscillator, a counter and a decoding circuit
5. 5. Calculating apparatus as claimed in claim 3 in which the numerical value is fed to the calculating circuit manually, and the function fed to the calculating circuit seq-uen- tially by means of an oscillator, a counter and a decoding circuit,
6. 6. Calculating apparatus as claimed in any preceding claim in which the means for indicating the functionally related value comprises an L.E.D. display.
7. 7. Calculating apparatus constructed

   and adapted to operate substantially as hereinbefore described with reference to Figure 1 or 2 of the accompanying drawings.