Classifications

• • G—PHYSICS
  • G07—CHECKING-DEVICES
  • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
  • G07C1/00—Registering, indicating or recording the time of events or elapsed time, e.g. time-recorders for work people
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
  • G01D21/00—Measuring or testing not otherwise provided for
  • G01D21/02—Measuring two or more variables by means not covered by a single other subclass
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
  • G01K3/00—Thermometers giving results other than momentary value of temperature
  • G01K3/02—Thermometers giving results other than momentary value of temperature giving means values; giving integrated values
  • G01K3/04—Thermometers giving results other than momentary value of temperature giving means values; giving integrated values in respect of time
• • G—PHYSICS
  • G04—HOROLOGY
  • G04F—TIME-INTERVAL MEASURING
  • G04F1/00—Apparatus which can be set and started to measure-off predetermined or adjustably-fixed time intervals without driving mechanisms, e.g. egg timers
  • G04F1/005—Apparatus which can be set and started to measure-off predetermined or adjustably-fixed time intervals without driving mechanisms, e.g. egg timers using electronic timing, e.g. counting means

Definitions

• the invention relates to an electrical expiry indicator according to the preamble of claims 1 and 2.
• data can be printed on that
• Such passive indicators can e.g. also on tickets, ski passes,
• Active indicators are those that automatically display a single time interval or periodically repeating time intervals.
• a tablet container is known from PE-PS 35 04 431, which has an adjustable interval signal transmitter, which is triggered when a first tablet is removed, and which emits a signal when the next interval in which the next tablet must be removed expires .
• an electrical aging indicator in which the change in a liquid level, which results from the diffusion of a liquid through a permeable wall, is used as an expiration indicator.
• the start time of a certain time interval can, for example. are triggered by the fact that the diffusion only begins after a cover film has been removed. The diffusion of such a liquid also depends on the prevailing temperature.
• JP-OS 62/172290 an indicator which has a timer which indicates the expiry of certain time periods in the form of a bar LCD. You can use this indicator an adhesive tape to be attached to objects.
• the expiry time should be changeable. In the case of foodstuffs, for example, the expiry date can also shift in the sense of an extension of the shelf life if appropriate cold storage is ensured. On the other hand, it may be necessary to indicate immediate uselessness when certain limit values, such as temperature or humidity, are exceeded.
• the invention has for its object to provide an electrical expiration indicator, the expiration time not only depends on the expiry of a certain period of time, but in which physical variables such as temperature, radiation, moisture and the like are taken into account as required.
• the solution specified in claim 1 is based on the known principle in which a counter is clock-controlled, that is to say a specific number of clock pulses corresponds to a specific time period.
• the clock frequency can be influenced as a function of a physical variable. This can e.g. can be achieved with a divider that divides the frequency of the pulses supplied to the counter.
• the divider should expediently have a certain working range in which the earliest possible and the latest possible expiry date lie. Irrespective of this working area, a count can expediently be provided, in which, regardless of the possible change in the expiry time, a display signal is generated after a certain period of time. that signals the decay.
• the solution proposed in claim 2 is based on the fact that the state of charge * of certain energy stores such as batteries, accumulators and capacitors is time-dependent, so this state can be used to implement an expiry indicator. If you discharge such an energy Storage via an electrical consumer, then you can record certain time sequences depending on the initial charge level and size of the consumer. The electrical consumer can in turn depend on a certain physical quantity.
• Such controllable electrical consumers can be, for example, bipolar transistors whose collector / emitter resistance is controlled via the base, or MOSFETs whose drain / source resistance can be controlled via the GATE electrode. The smaller the resistance value, the faster the energy is drawn. If an inadmissible value occurs, for example for foods that have been exposed to an excessive temperature, the energy store is suddenly discharged.
• the operating mode of such an energy storage device is expediently chosen so that at the possible time of decay there is still a certain residual energy which is sufficient to trigger a display signal.
• LCD elements with which a color change and / or a symbol change can be implemented are particularly suitable for such displays.
• a bistable display device is expediently used, which changes to the stable state when the expiry time is reached and thus enables a display to be made regardless of the remaining energy.
• the energy store must be rechargeable, for example in the form of an accumulator.
• the energy storage device can be connected in parallel with the series connection of a rectifier and a coil.
• An alternating magnetic field induced by the coil from the outside then serves for recharging.
• the duration and intensity of the magnetic field determine the stored energy.
• Such coils can be made very thin as printed coils and are therefore suitable for flexible indicators that have to be applied to curved surfaces.
• the others too Elements of such an indicator can be designed to be sufficiently mechanically flexible.
• LCD display elements that are flexible are also known. For this purpose, the top and bottom are not made of glass, but of plastic.
• Fig. 1 is a block diagram of an electronic circuit
• Fig. 2 shows the basic structure of those used in the indicator of Fig. 1
• the electronics 5 also contains an evaluation circuit 8 which evaluates signals generated by sensors 4 as a function of information and commands stored in a memory 9. In this way it is possible, for example, that the signal generated by a temperature sensor is evaluated in such a way that the frequency of the clock pulses of the oscillator 3. As a result, the expiry time shifts accordingly, so that the display device switches on at an earlier point in time
• the actual power supply in the form of energy storage 9 is used directly to record the expiration time.
• the energy store 9 works via a fuse 12 on a controllable resistor 10, which via a control line 11 depending on a specific physical
• Size is changeable. As soon as the energy of the memory 9 has reached a certain residual value, one cannot. Display device shown are triggered to signal the expiry time.
• the fuse 12 is used to prevent the device from being restarted and thus to prevent the expiry indicator from being tampered with.
• Fig. 4 shows an embodiment in which the controllable resistor 10 additionally contains a switch 13, so that instead of a constant discharge, only a discharge which is dependent on the duration of the closed state of the switch takes place, so that there is a corresponding extension of the discharge time period.
• FIG. 5 shows the possibility of recharging the energy store 9 via the series connection of a rectifier 15 and a coil 14, in which an alternating magnetic field can be induced for charging.

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Measurement Of Unknown Time Intervals (AREA)
• Electric Clocks (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=6392751

Family Applications (1)

Country Status (3)

Cited By (5)

Families Citing this family (4)

Family Cites Families (13)

• 1989
  • 1989-11-02 DE DE19893936543 patent/DE3936543A1/de active Granted
• 1990
  • 1990-10-24 WO PCT/EP1990/001806 patent/WO1991006838A2/de not_active Ceased
  • 1990-10-24 AU AU66073/90A patent/AU6607390A/en not_active Abandoned

Also Published As

Similar Documents

Legal Events