GB2173616A - Temperature measuring calculator - Google Patents

Abstract

An electronic calculator incorporates an internal sensor 6 for measuring temperature. The temperature measurement is processed by the calculator chip to provide displays of temperature. A socket is provided for connection of an external temperature sensor 10 by a flexible conductor 9 and plug 8. Connection of the external sensor automatically disconnects the internal sensor. The standard calculator keyboard is supplemented by a selector switch for "calculator" or "temperature". <IMAGE>

Description

SPECIFICATION Temperature measuring calculator This invention relates to electronic devices of the kind commonly called calculators and in particularto pocket calculators.

According to one aspect of the present invention there is provided an electronic calculator, incorporating a transducer responsive to a physical quantity and connected to the calculator processing and display means whereby the calculator is operable as a measuring device for the said quantity.

According to another aspect of the present invention there is provided an electroniccalculatorcomprising in combination, as a single unit, a LSI microprocessor, a keyboard and a display connected thereto, and a transducer responsive to a physical quantity, the transducer being connected to the microprocessor, and the latter being designed and/or programmed to perform calculatorfunctions in conjunction with the keyboard and display and to process the signals provided by the transducer and to display the results of such processing.

The transducer can for example be a wheel or other distance measurer and in this case the processor is preferably set up so as to calculate areas orvolumes from the measured distances.

In another embodiment the transducer is a temperature sensor. Preferably, means are provided foradditi onally connecting an external temperature sensor, for convenience of measurement.

In a further embodiment, the transducer is sensitive to light. In this case, the processor is arranged so that the calculator can function also as a photographic light meter.

In a further embodimentthetransduceris a weight sensor. This embodiment will usually be a deskortable top calculator ratherthan a pocket calculator, and in a preferred arrangement the processor is arranged to calculate postal charges ofthe articles weighed, on the basis of programmed postal rates.

The processor may be a common chip designed to perform all the above-mentioned functions, selection of particularfunctions being effected by particular external connections ofthe processor chip. Thus, a common chip can be used in calculators having different types oftransducer.

Embodiments of the invention are illustrated by the accompanying drawings, in which: Figures land 2 are top and end views of a calculator incorporating a distance measurer, Figures 3to 5are plan, side and end views of a calculator with internal and external temperature sensors, Figures 6and 7are plan and end views of a combined calculator and photographic exposure meter, Figures 8 and 9 are plan and side views of a combined calculator and postal scales, Figure 10 is a block diagram of a calculator with a transducer, and Figure 11 is a simplified flow chart of one form of processor.

Figures 1 and 2 show a pocket calculator with a casing 1 of suitable size, provided with a keyboard 2 and a display window 3. In addition to conventional data entry keys, arithmetic operation keys and command keys, the keyboard includes a selector switch 4 and keys for ENTER, RESET, RECALL, AREA and VOLUME. These are associated with five data registers and processing circuitry in the calculator chip, and a distance measuring wheel 5 which projects from one corner of the casing and drives a suitable transducer so as to produce electrical signals in proportion to the revolutions of the wheel.

With the selector switch set to "cal", normal calculator functions are obtained through the use ofthe keyboard. With the selector switch set to "dimension", the calculator can be used to measure distances, by rolling the wheel 5 along a line or object to be measured. The measured distance can be temporarily stored, processed in order to calculate the area of a measured Figure or the volume of a measured object, and displayed. More specifically, the following functions are provided: RESET- Pressed, eventcounterand display are resettozero.

ENTER - Pressed, store the distance displayed into one of the five (5 data registers indicated by a data register pointer. Increment data register pointer.

RECALL - Pressed, recall data from the data register indicated by the data register pointer, display data and increment data register point. If pointer is pointing at the fifth register, when pressed, pointer will be set to first data register.

M + M - - Pressed, add or subtract the displayed number into or from the memory register respectively.

MCr- Pressed, recall data of the memory register to the display register.

Successive depressions will clear the memory register.

AREA- Pressed, calculate area from measured distances according to equations below the equation used depending on the position of the data register pointer. Store result at area register.

Set status bit to ' 1' .

VOLUME - Pressed, calculate volume from measured distances according to equations below, the equation used dpending on the position of the data register pointer and status bit.

CE/C - Pressed, clear all registers and set pointer to position 1. Set status bitto '0'.

Pointerpos. equation Area Triangle 4st(0) > /s(s-a)(s-b)(s-c),s=1/2 [ a+b+c) Square 3 st(0) a2 Rectangle 3 st(0) (a)(b) Circle 2 st(0) (p2)/(4#) Vol- Cube 4st(0) a3 ume Parallelogram 4st(0) (a)(b)(c) - 2 st(0) (p3)/(6#2) Circ Cylinder 3 st(1) (area of circle)(h) Tri. Prism 5st(1) (area oftriangle)(h) a,b,c = length of sides p = circumference h = length Thus to measure and display a length the operations are: Reset (R) - measure - enter (E).

To measure areas key sequences are: Square: R # measure side # E # E #key AREA (A) Rectangle: R # measure side a # E # R # measure side b # # E # A Circle: R emeasure circumferencee EA Triangle R # measure side a # E # R # measure side b # E # R # measure side c # E # # A The keying sequence for measuring volumes are: Cube: Ro measure sideo Eo Eo Eekeyvolume (v) Cuboid:R- > measure side a # ER measure side be # E # R # measure side c # E # # V Sphere R # measure circumference # E # V Prism R # measure side a # E # R # measure side B # # E # R # measure side c # E # A # # R # measure lenght # E # V Cyl:R # measure circumference # E # A # R # # measure lenght # E # V As the measuring wheel can produce outputs in the form of pulses, the transducer output can be connected substantially directly to an event counter of the processing circuitry, operating for example atone centimetre per pulse, or at a greater frequency for more accurate measurement.

Figures 3to 5 show another pocket calculator, which as an internal temperature sensor 6 and a socket7for connection of an external temperature sensor 10 by means of a flexible conductor 9 and a plug 8. The standard calculator keyboard is supplemented by a selector switch for "calculator" or "temperature" and buttonsfor RECALL, ENTER, F and C. Connection of the external sensor automatically disconnects the internal sensor.

The sensors are of any convenienttype, sensitive for example minus 50to 150 C. The sensors are connected to the processing circuitry'through a voltage-frequency converting interface with a frequency range of for example 4 kKzto 8kHz, and the processing circuitry includes a frequency counter operating at Hz pert.

Temperature can be displayed in C or F. A displayed temperature, either measured or entered through the keyboard, can be converted from Fto t orviceversa, by operation of the corresponding temperature scale key.

With the selector switch set "Calculator" the usual calculator functions are available. With the selector switch set to "temperature", temperature is measured by placing the internal or external temperature sensor on the object or in the area of which the temperature is to be measured, and pressing the ENTER key. Five temperature data registers are provided so thatfive temperatures can be stored. Key operation is as follows: ENTER-Pressed, store temperature displayed into one of the five (5) data registers indicated by the data register pointer. Increment data register pointer.

RECALL - Pressed, recall data from the data register indicated by the data register pointed, display data and increment data register pointer. If the position of the pointer is at the fifth data register, pointer is set to point at the first register.

F- 1. during measurement, when pressed, display in F 2. during conversion, pressed before key-in data indicate key-in data is F.

3. during conversion, pressed after key-in data indicate key-in data is to be converted to F.

t - similarto the 'F key, except all F replaced by t.

CE/C- clear all registers and set data register pointerto position 1.

The calculator shown in Figures 6 and 7 has, in addition to its calculator keyboard 2 and display 3, a built-in light sensor behind a diffusorwindow 12 at one end of the calculator casing. The light sensor is connected through a voltage-frequency converter to a frequency counter of the processing circuitry which is programmed to convert the measured voltage/frequency into light intensity according to a suitable characteristic equation.

The keyboard has a selectorswitch 13 to select calculator or light meter operation, a peak detection selector switch 14, and additional keys as follows: ENTER - Pressed, store key-in value into the relevant register. They are A.S.A., aperture and shutter. Or store measured lux value into lux register.

A.S.A. - Pressed to indicate the following key-in data is the reciprocal of shutter speed.

APERTURE - Pressed to indicatethefollowing key-in data is the aperture value.

(note: new entered data will write over the contents ofthe register.

To enter data, press the data-indentifying key, enter the value using the keyboard, and press the ENTER key.

In use: (1) Switch "Cal/lux" key 13to "lux position.

(2) For peak detection, lock peak switch 14to'on' position unitto record peak reading displayed.

(3) For normal operation, position meter and take reading from display.

(4) Press ENTER key to store instantaneous reading.

(5) Enter shutter speed and press Aperture to display aperture value, or (6) Enter aperture value and press Shutterto display shutter speed.

The PEAK setting is for use with flash: the flash is triggered,the display shows the peak light value, and this can be stored by pressing ENTER.

The display is controlled to include indicators showing whetherthe displayed value is film speed, aperture, shutter or light intensity, and may include a "LOW" warning for either shutter speed or aperture value.

Facilities for measurement and display using DIN film speed units may be included.

The three calculators described above are all small pocket calculators, using primary or secondary batteries and preferably having LCD displays to conserve power.

Figures 8 and 9 show a desk calculator (which accordingly can have a connectorforan AC supply adaptor, and a LED display or printer if desired), incorporating a letter-weighing device. The latter comprises a platform 15 Sat the rear of the calculator casing, operating any suitable electrical or electro-mechanical load sensor which is connected to the calculator processing circuitry through a voltage-frequency interface driving a frequency counter, operating at for example 8Hz/grm over a frequency range four kHzto eight kHz, corresponding to a weighing range of O to 500 grms.

A zero-setting control 16 is provided forthe weighing platform.

The illustrated device is designed to have a general appearance similar to a conventional desktop calculator.

Alternatively, the device can be designed as a decorative object.

The calculator has a conventional keyboard supplemented by keys to select local and foreign and postal rates, and selector switches for selecting operation as a calculator or as a weighing device, and for selecting a programming mode enabling the user to enter into respective registers the postal charge rates corresponding to different weights forforeign and local mail.

Postal rate programming (1)Switch program switch 17 to 'ON' (2) Enter postal rates for each of the available zones by pressing FOREIGN and N or LOCAL and N keys.

(NOTE: N is the numerical key(s).) (3) Number of memories available is 6.

Weighing (1) Switch 'Cal/Weight' Switch 18 to 'Weight' position.

(2) Place object on scale, weight is displayed.

(3) Select postal rate by either pressing FOREIGN and N keys or LOCAL and N keys.

(4) Data displayed is the actual postal charge.

The display will show the actual value, whether the foreign or local rate is applicable, and whether the object is overweight.

Dedicated chips incorporating the necessary interface and counter circuitry as well as the processing and control circuitry can be provided for each of the calculators described. The hardware for each calculator is generally as shown in Figure 10, comprising the keyboard 2, display 3 (for example an eight-digit LCD) a micro computer 19 with suitable counting and register circuits, the appropriate transducer 20 and an interface 21 if required between the transducer and the micro computer. The transducer senses the parameterto be measured and provides a voltage output representing, and preferably proportional to, the value ofthe parameter.The interface (not essential for the distance measurer) converts voltage to frequency, providing a signal which the micro computer can process in digital fashion using its counting circuitry.

We envisage that programs for all of the fourfunctions described (distance measurement, temperature measurement, light measurement and weighing) together with the calculator program will be provided on a single LSI chip, the selection of the program required for any particular calculator device being by suitable external connection ofthe chip. Figure 11 shows a simplified flow chartfora common LSI chip ofthis nature.

The flowchart is self-explanatory and is therefore notfurther described.

Our application No. 8222001 from which this application is divided describes and claims a calculator provided with means for weight measurement; ourcopending application also divided from Application 8222001 describes and claims a calculator provided with meansfortemperature measurement.

Claims (3)

1. An electronic calculator comprising in combination as a single unit, a LSI microprocessor, a keyboard and a display connected thereto, and a distance measuring transducer,thetransducer being connected to the microprocessor, and the latter being designed and/or programmed to perform calculatorfunctionsinconjunc tion with the keyboard and display and to process the signals provided by the transducer and to displaythe results of such processing, the calculator being adapted to and to calculate areas of volumesfrom measured distances.

2. An electronic calculator, incorporating a distance measuring transducer connected to the calculator processing and display meanswherebythe calculator is operated as a distance measuring device, the calculator being adapted to and to calculate areas orvolumesfrom measured distances.

3. An electronic calculatorsubstantially as herein described with reference to Figures 1 and 2 of the accompanying drawings.