Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
  • G01K7/00—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements
  • G01K7/16—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements
  • G01K7/18—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a linear resistance, e.g. platinum resistance thermometer
  • G01K7/20—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a linear resistance, e.g. platinum resistance thermometer in a specially-adapted circuit, e.g. bridge circuit
  • G01K7/203—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a linear resistance, e.g. platinum resistance thermometer in a specially-adapted circuit, e.g. bridge circuit in an oscillator circuit
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F15/00—Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus
  • G01F15/07—Integration to give total flow, e.g. using mechanically-operated integrating mechanism
  • G01F15/075—Integration to give total flow, e.g. using mechanically-operated integrating mechanism using electrically-operated integrating means
  • G01F15/0755—Integration to give total flow, e.g. using mechanically-operated integrating mechanism using electrically-operated integrating means involving digital counting
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
  • G01K17/00—Measuring quantity of heat
  • G01K17/06—Measuring quantity of heat conveyed by flowing media, e.g. in heating systems e.g. the quantity of heat in a transporting medium, delivered to or consumed in an expenditure device
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
  • G01K7/00—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements
  • G01K7/16—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements
  • G01K7/22—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a non-linear resistance, e.g. thermistor
  • G01K7/24—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a non-linear resistance, e.g. thermistor in a specially-adapted circuit, e.g. bridge circuit
  • G01K7/245—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a non-linear resistance, e.g. thermistor in a specially-adapted circuit, e.g. bridge circuit in an oscillator circuit

Definitions

• the present invention relates to a pulse counter circuit according to the preamble of the main claim.
• Such pulse counter circuits are used in particular for throughput measurements and are preferably used here for heat quantity measuring circuits. It is necessary for the throughput to be measured within a certain time unit through a pipe, in particular a supply or return line from a central heating system.
• a vane measuring wheel can be provided which emits pulses to a measuring line via a magnetic pulse generating device, the number of pulses being therefore a direct measure of the volume passed through. If the impulse is limited by a certain time, the throughput per unit of time can be determined. In order to be able to make reasonably accurate measurements here, it is necessary to keep the time in which the pulse count takes place relatively long. On the other hand, it is expensive to reproducibly generate long times with electronic means.
• the present invention is based on the object of specifying a pulse counter circuit with which an accurate counting of pulses occurring over a certain period of time is possible, but which is considerably cheaper to set up than the prior art. This problem is solved with the characterizing features of the main claim.
• Figure one shows a basic circuit of the invention
• a pulse counter circuit for example for a throughput measurement for tap water, has a frequency-controlled oscillator 1, to which a measuring resistor 4 with a positive or negative temperature coefficient is connected via lines 2 and 3. This measuring resistor senses the temperature of the tap, its resistance value is directly variable with the temperature of the water.
• a pulse voltage 6 is present at the output 5 of the oscillator 1 and is fed to a period discriminator 8 via the line 7.
• a pulse duration 10 having a period duration 9, which is connected via a line 11 to the one input of a gate circuit 16.
• An electrical start signal is fed to the period discriminator via a start line 12.
• a frequency constant oscillator 13 gives over a line 14, a pulse voltage 15 with a constant frequency and onto the second input of the gate circuit 16 designed as an AND element 16.
• a pulse voltage 19 is thus present at the output 17 of the AND element 16 for a period 9, which corresponds to the pulse voltage 15 in this respect .
• the line 17 is given to a pulse counter 18.
• the circuit just described works as follows: With the measuring resistor 4 the temperature of a tap water or a heating water pipe is sensed, this measured value is switched to the oscillator 1. At the output of the oscillator there is therefore a frequency F 1 which, according to curve 6 in FIG. 2, has a certain period. This period is considerably longer than the period of the pulse voltage 15. The oscillator 13 continuously generates a pulse voltage FK 15 which is constant in frequency. The frequency of the voltage 15 is significantly greater than that of the voltage 6. As long as there is no signal on the line 11, the AND element 16 is blocked, that is to say that no counts reach the counter 18. The period discriminator 8 blocks the output until a start pulse 20 is fed to it via line 12.
• the period discriminator opens its output 11 for the next period 9 of the pulse voltage 6. For this period there is voltage on line 11 and thus on one input of the AND element 16, so that the pulses on line 14 from the frequency-constant oscillator be allowed through.
• the counter 18 thus counts as many pulses of the pulse voltage 15 as the period 9 is long.
• the period discriminator 8 only allows one period 9 to pass when a start pulse is applied to the line 12. It would also be possible to give output voltage to output 11 for several periods, provided that the counting result of the count lers 18 is then divided by the number of periods.
• the counter 18 accordingly counts the more pulses, the longer the period 9 of the pulse voltage 10 lasts.
• the counter reading in the counter 18 is thus a direct and immediate measure of the variable, in particular the temperature, measured by the measuring resistor 4.
• the And element 16 locks again.

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• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Nonlinear Science (AREA)
• Fluid Mechanics (AREA)
• Measuring Volume Flow (AREA)

Applications Claiming Priority (2)

Publications (1)

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ID=6737543

Family Applications (1)

Country Status (4)

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• 1983
  • 1983-02-05 WO PCT/DE1983/000022 patent/WO1983003002A1/de not_active Ceased
  • 1983-02-05 EP EP83900488A patent/EP0101447A1/de not_active Withdrawn
  • 1983-02-22 IT ITMI1983U20885U patent/IT8320885U1/it unknown
  • 1983-09-28 DK DK4434/83A patent/DK443483D0/da not_active Application Discontinuation

Non-Patent Citations (1)

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