Data processing and recording apparatus

A low-cost data logging device, particularly suitable for recording gas meter performance having an electrical transducer to produce an electrical analogue of a parameter to be recorded, a calculator circuit to perform an analysis of measurements of the parameter and a plurality of memories to store the results of the analyses.

BACKGROUND OF THE INVENTION 
1. Field of the Invention: 
This invention relates to data processing and recording apparatus and, in 
particular, to apparatus for recording information about the flow of 
fluids through a metering device such as a gas flow meter. 
2. Description of the Prior Art: 
Information concerning daily or hourly variations in load for industrial or 
commercial consumers is of considerable value, inter alia, for monitoring 
or controlling peak daily loads, checking the correct dimensioning of 
meter installations, checking spare meter capacity available for load 
increases and the determination of standard load factors to assist in the 
design of new installations. 
Hitherto such data have been collected manually or by means of conventional 
data logging equipment. However, such applications have been limited to 
special cases because of the relatively high costs involved. 
In order to extend the range of applications for which it is feasible to 
employ data logging methods a new, simple data recording apparatus has 
been devised. 
SUMMARY OF THE INVENTION 
According to the present invention there is provided data recording 
apparatus comprising transducer means to produce an electrical signal 
representative of the magnitude of a parameter to be recorded, digital 
analyzing means to determine whether or not the magnitude of the parameter 
falls within predetermined limits and a plurality of data storage means 
each corresponding to a range between predetermined limits of said 
parameter to record the incidence of a measurement of said parameter 
within the respective predetermined limits. 
According to a further aspect of the invention, the data recording 
apparatus includes timing means to permit the measurement of said 
parameter at predetermined intervals. 
According to a yet further aspect of the invention there is provided means 
associated with said data recording apparatus to prepare a permanent 
record of successive measurements of said parameter.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring now to FIG. 1 of the drawings, a calculator circuit incorporates 
a keyboard 1 having a plurality of keys 2 for input of data and program 
instructions. The keyboard is linked to a scan encoder 3 by way of a bus 4 
consisting of a plurality of scan lines connected in matrix fashion to the 
keys. An arithmetic unit 5 in association with an input register 6 and an 
accumulator 7 performs various operations on the input data under the 
control of programs stored in a memory 8. The memory may comprise ROM 
(Read Only Memory) for standard operations such as addition, subtraction 
and exponentiation which are called up by respective function keys on the 
keyboard or RAM (Random Access Memory) in which the steps of an individual 
program may be entered. An output encoder 9 transfers the processed data 
from a temporary store 10 to an output device 11 which may be a 
seven-segment digital display or a printer. Timer circuits 12 and a clock 
13 synchronize the movement of data within the calculator circuit. Power 
is supplied from a DC source 14 which may be a battery or a mains unit. 
With data recording apparatus in accordance with the embodiment of the 
invention depicted in FIG. 2 a gas flow recording meter has a transducer 
15 which provides an electrical signal corresponding to the mechanical 
meter reading. This signal may typically be a digital pulse emitted 
whenever a predetermined quantity of gas has passed through the meter. 
In one embodiment, the digital pulse was fed via an input circuit 16 to 
simulate the operation of selected keys whereby a section of program 
within the calculator was initiated so that, by reference to the 
calculator clock, the interval between pulses was timed and data stored in 
various registers according to the flow rate passing through the meter at 
the time. A typical field measurement is shown in Table 1. 
TABLE 1 
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Meter size 140,000 ft.sup.3 /hr tested over 21 days 
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Flow range 0-20 20-40 40-60 60-80 80-100 
% of meter capacity 
% of flow recorded 
2.5 78 19.5 0 0 
in range 
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In a further embodiment a clock gave a timing pulse at predetermined 
intervals (1 day) and the pulses were used to activate successive memories 
to record the flow passed by the meter during successive time intervals. 
As the number of memories was finite, data were transformed to individual 
memories in a cyclic fashion so that data from the most recent 
measurements were preserved. 
Using the programming capabilities of the calculator circuit analyses of 
the data can be performed and a summary of the results stored in the 
memories. For example one simple program recorded maximum hourly load, 
minimum hourly load, number of hours in which flow exceeded a 
predetermined rate, number of hours in which flow was below a second 
predetermined rate and the total flow. 
Preferably the keyboard unit is detachable by means of a plug and socket 
connection, thereby obviating the possibility of the data processing 
program being inadvertently altered by an unskilled person. 
A further embodiment included a thermal printer which recorded successive 
readings. Typical printouts are shown in FIGS. 3a and 3b which shows 
outputs in numeric and graphical formats respectively.