EP0439725B1 - Autonomous radio-controlled clock - Google Patents

Description

The invention relates to a radio clock according to the preamble of claim 1.

Such a radio clock is known from DE-A-30 43 867. The problem of the detection of time information in the radio signal received with interference is to be promoted there by manually presetting the most currently known partial information, so that a derivation from the demodulated and decoded radio information is required, which promotes the correlation comparison of the time information. The non-critical scope of information definitely captures the year, since the user of the watch is usually familiar with the year in which he is currently living. The current month and the current date including day of the week are also likely to be familiar and are therefore specified manually for the clock. What is the current hour or even minute is less certain, and the currently correct second must be obtained from the radio information in any case for the running operation of the watch. If the manual specifications via radio could then also be confirmed (and corrected if necessary), the manual intervention in the current time display is blocked and only released again if the radio clock has to start again after an interruption in operation under unfavorable reception conditions. The publication does not take into account the time-varying time displays transmitted by radio, in particular for the operation of the clock in neighboring time zones.

A radio clock is therefore not to be understood as a (for example also portable on the arm) receiving device for radio or television program broadcasts or for paging systems, which can also be equipped with a clock; Rather, a radio-controlled clock of the generic type is a receiver which, for the periodic reception of coded absolute time information, is permanently tuned to at least one transmitter (generally in the long-wave range) in order to derive a time display from the decoded information. In the case of an autonomous radio clock, an internal time-keeping circuit is additionally provided in order to advance the time display even when - for example when the battery-operated radio clock is switched off to save energy or because of radio transmission interference - no valid time information is received.

The function of the clock known from JP-A-53 003 870 (corresponding to Patent Abstracts of Japan, Vol. 2, No. 40 (E-78, March 16, 1978)) deviates from this conventional radio clock in the actual sense insofar as it It is actually a conventional electronic watch, with the special feature that the user can manually switch on a transmitter for reception and decoding of absolute time information distributed via radio to check and, if necessary, correct the current time display, but this distorts the time display if the The transmitter currently being received is not coded for the time zone in which the clock is currently being operated. Also, DE-A-25 30 985 is not a generic radio clock in the more strict sense than the clock built into a computer only and only displays a time when the receiver is switched on for this purpose and actually receives usable time information When the computer is switched off, all time information is also deleted.

Basically, a radio clock does not require any operating device at all, because when the operating energy is made available, the receiver is switched on in order to set the display of the internal autonomous time keeping and to correct it from time to time, as is the case with reference to the time telegram in the circuit description U. Berger "DCF-77 clock with microprocessor" in FUNKSCHAU volume 50 No. 12 from June 1978, pages 579 to 582, is explained. If the EP-A-0 308 881 is nevertheless equipped with manually operated pushbuttons, then not to influence the radio-controlled time display, but only to specify an alarm time and to switch off a signal triggered when this time is reached.

According to JP-A-61 144 588 according to Patent Abstracts of Japan, Vol. 10 No. 341 (P-517) (2397), 11/18/1986, an electronic watch can be put into a battery-saving sleep state, for example when it is delivered from the factory and until it is sold to the end customer, by means of a time evaluation of the specified rhythm of a manual key operation is queried.

In contrast, the invention is based on the object of promoting a radio-controlled watch of the generic type in its intended use by overcoming the basic difficulties in use as a functional, small, portable watch, for example in the sense of a travel alarm clock or a wristwatch, which inevitably occur during operation outside of the geographical time zone for which the currently received time telegram transmitter is operated.

This object is achieved by a radio clock with the features of claim 1.

This solution allows switching to a time display with the same accuracy but in neighboring time zones and finally also the operation and even the start-up of the clock itself, far away from the transmitter-related time zone, without having to fear that there by accidental or playful triggered receiver switch-on a time information that is actually not usable falsifies the previously applicable time display. At the same time, the switching device available for this time zone changeover enables the clock to be put into the extremely power-saving sleep operating state in a manner known per se by manual actuation of the switch, from which it is then possible to return to the normal operating state with automatic adjustment to the received by simply pressing a button. current legal time can be returned.

Additional alternatives and further developments, as well as further features of the invention, also taking into account the explanations in the summary, result from the following description of a preferred implementation example for the solution according to the invention shown in the drawing, limited to the essentials; in order to promote understanding in the description of the drawing, it is not the module connections themselves that are addressed, but rather the incoming or outgoing signals there.

The only figure in the drawing shows, symbolically simplified, a small, autonomous radio-controlled clock 11, configured as a wristwatch, with a receiver 12 tuned to a time telegram transmitter and, if necessary, tunable. This is fed from an antenna 13, which is a magnetic antenna 13 can act with an antenna coil on a flexible core, embedded in a watch strap connected to the housing 20 (not shown). The absolute time information 14 output by the receiver 12 after demodulation of the radio reception signal is transferred to a register 15, which is then clocked further by an internally autonomous time-keeping circuit 16 in order to periodically supply control signals 17 for the time display device 18. This can be designed as an electro-optical display or as an electromechanical display device for the presentation of analog or digital information. In the case of an electromechanical display device 18, this provides a feedback signal 19 about the current display position (i.e. about the current angular position of pointers or the positioning of numerical flaps), in order to correct the display by the register 15 if the time information currently contained in the time memory 35 deviates trigger, as known as such in generic radio clocks.

In addition, the radio-controlled watch housing 20 is equipped with a manually accessible and actuable multifunction switching device 21, which preferably contains three individually actuatable pushbuttons 22. Their current actuation combination is decrypted in a decoder 23 and is used to control the aforementioned functional elements of the radio clock 11.

A test cycle can be run through this switching device 21, for example in the course of the quality inspection at the end of production, which is of particular interest when an electro-optical display device 18 is used. For this purpose, the decoder 23 delivers a test signal 24 when two pushbuttons 22 (for example the upper and the lower) are pressed simultaneously and also during this time the remaining third pushbutton 22.2 is only temporarily pressed - that is, an actuation of the switching device 21, which is not done accidentally and because of the recessed pushbutton 22 is best carried out using an appropriate multi-punch tool (not shown). The test signal 24 results in a count signal 24 ', which counts all the display elements of the electro-optical display device.

In order to minimize the energy consumption of such a battery-powered radio-controlled clock 11 after a successful final production test, the entirety of all its circuit arrangements is put into a "sleep" mode in that the decoder 23 outputs a saving signal 25 by simultaneously actuating two pushbuttons, for example 22.2 and 22.3 This causes the function of the radio clock 11 to be switched off, but a corresponding information appears on the display device 18 to make it clear that the clock 11 or its display device 18 are not defective, and returning to the operating state is simple can be triggered by briefly pressing any one of the pushbuttons 22.

In order to ensure a defined function start, the entire evaluation circuit is then expediently set to a defined initial state; which should also not be done erroneously, which is why only a multi-button operation, for example push buttons 22.1 and 22.2, triggers the so-called system reset 26. As a result, not only are all memories erased, but in particular a processor, by means of which register 15 and decoder 23 are controlled, is set to a defined initial program state for an error-free start in the program sequence.

With the start-up (from the sleep mode or, for example, as a result of replacing the battery for the operation of the radio clock 11), a switch-on signal 27 is sent to the receiver 12 and a flashing indicator 28 indicating the reception operation is triggered. This also starts the internal time-keeping circuit 16, so that internal time information on the display device 18 (in particular its seconds display) is counted up. However, as soon as the receiver 12 supplies usable time information 14, the display device 18 switches over to its presentation in a special area 29 (such as the calendar display) in order to thereby express that radio time information is already present 14 - but still no absolutely secure time information 14 - is presented. Only when current absolute time information 14 secured by comparison of successive time information has appeared will this complete information be presented in the time display normal area 30 of the display device 18 in the future, in the case of an electro-optical digital display, that is, by hour, minute and second numerical representations. The receiver switch-on signal 27 thus disappears again, but the internal time-keeping circuit 16, once started, continues to run. When the receiver 12 is switched off, the reception display 28 also disappears and the information presentation on the display normal area 30 is now clocked out of the internal time-keeping circuit 16. However, at times specified in register 15, such as daily at 2 a.m., a new switch-on signal 27 is triggered in order, if necessary, to correct the current time presentation on the normal range 30 of the display device 18 if they deviate from the absolute time determined by radio should.

The reception range of the receiver-antenna combination 12-13 typically extends not only over the one time zone in which the time telegram transmitter (such as the transmitter DCF 77) to which the receiver 12 is tuned is installed, but also far into the geographic time zones neighboring on both sides.

In order to leave the geographical time zone with the time display, on whose time telegram transmitter the receiver 12 is tuned, only the currently displayed hours need to be counted up or down in hourly steps, with the minute and second presentations not being influenced. This can be done by correspondingly frequent actuation of the pushbuttons 12.3 or 12.1, which switch the corresponding hour addition or subtraction signals 31, 32 via the register 15 to the time memory 35 for the display device 18.

When there is a time zone adjacent to the transmitter, each time information 14 received is switched back to the hourly time display according to the original time zone, which can then be corrected manually, as described, by actuating a push button 22.3 or 22.1. Beyond the time zones adjacent on both sides, however, the probability is then too low that the receiver 12 can still supply usable time information 14. In order to exclude incorrect displays or display misinterpretations or unnecessary display interruptions during attempts to receive, which are likely to be unsuccessful, a blocking signal 33 is therefore sent to the receiver 12, which deactivates it as long as the manually adjusted hour display deviates from that by more than one hour , which would be applicable according to the time information 14 in the vicinity of the transmitter.

This blockage of the receiver 12 in the power-saving switch-off position can be removed by either reversing the manual adjustment of the hour display via the push buttons 22.1 or 22.3; or the time memory 35 containing this hour adjustment is reset to its zero initial state in the register 15 by restarting in accordance with the above-described start-up (by inserting the battery or by ending sleep mode). This resetting of the time memory 35 with deletion of the display 18 can, however, also always be brought about by keeping one of the pushbuttons 22.2 pressed for a defined minimum length, which can be queried by a time switch 34 in the decoder 23. In this case, it delivers a reset signal 36 to the time memory 35, which means that the blocking signal 33 can also be released. When the push button 22.2 actuated over the relevant minimum period of time is released, the presentation in the normal display area 30, controlled by the internal time-keeping circuit 16, begins to count up. After that, only the current hour display has to be set up by means of the manually triggerable addition or subtraction signals 31, 32. For example, the acoustic recording of an hourly time stamp transmitted via program broadcasting, for example, can start the minute and second display manually at the exact hour if there is no contact with the relevant station at the time the watch is started due to the currently unfavorable reception conditions. However, the switched on receiver 12 tries to replace this manual start display as soon as possible with confirmed absolute time information 14.

If, on the other hand, this reset pushbutton 22.2 is actuated only briefly during normal operation of the radio clock 11, the time separator 34 instead supplies a switch-on signal 27 'acting on the receiver 12. This so-called "transmitter call" deletes the presentation in the normal area 30 of the display device 11, but the time memory 35 is not reset, but is clocked further from the autonomous time-keeping circuit 16. If the receiver 12 which is now switched on has a time compared to the updated time information in the memory 35 or provides plausible time information 14 in comparison to previously received time information 14, it is transferred to the time memory 35 and for display purposes, otherwise the internally advanced time information is transferred from the memory 35 to the display device 18 again, namely over a certain predetermined reception time period the receiver 12 is not due to, for example, disturbed radio transmission conditions is able to provide plausible time information 14. As a result, the absolute correctness of the time information that was then displayed again was not confirmed by radio, but is nevertheless given with a sufficiently high probability because it is the display of the internally continued earlier time display; without the time presentation being finally interrupted (until the periodically switching on receiver 12 once again provided correct time information 14). This mere display reset function, which can be triggered via the "transmitter call" button 22.2, is expediently prevented by a blocking signal 38 when the hours are manually adjusted beyond the adjacent time zones, since, as said, a sufficiently reliable reception of radio time telegrams is no longer to be expected anyway .

The display device 18 expediently also has a control display 37 on which numerical figures can be displayed from the register 15, since when (for example for how many days), if appropriate, the temporary switching on of the receiver 12 automatically at night by means of a switch-on signal 27 ″ not for decoding a usable current time information 14. However, this control display 17 is also incremented by one unit if the receiver 12 was put into operation with the so-called "transmitter call button", the push button 22.2, via the manual switch-on signal 27 '; the receiver 12 then switches off again after a certain operating period to save electricity without real time information 14. If the display volume of the control display 37 is fully counted, ie in the case of a single-digit digital display after nine unsuccessful activation of the receiver, the highest display remains It is reset to zero when the automatic or manual switch-on of the receiver leads to the recovery of usable time information 14.

The control display 37 can be structurally combined with the reception display 28 by making the control number flash when and as long as the clock 11 is on reception. In order to avoid any irritation, the control display 37 is then expediently switched off completely if it would display "zero", since the current time display could be confirmed when reception was switched on in the past.

Claims (5)

1. A small-size autonomous radio-controlled clock (11), in particular in a design as a small travel alarm or as a wristwatch, with a receiver (12) for coded items of time information (14) for controlling a display device (18) which, with the receiver (12) switched off, is stepped-on from an internal timekeeping circuit (16), and with pushbuttons (22) for manually influencing the content of the display device (18), characterised in that a manual hours-display adjustment is provided and, in the event of more than one hour's deviation from the items of time information (14) received by radio, an otherwise automatically recurring switch- on of the receiver (12) is blocked.

2. A radio-controlled clock according to claim 1, characterised in that, upon manual adjustment of the hours display by more than one hour's deviation from the items of time information (14) received by radio, only a complete manual system reset (restart) but not a manual receiver switch- on along with internal continuation of the time register (transmitter call) is possible.

3. A radio-controlled clock according to claim 2, characterised in that associated with a reset push-button (22.2) is a time switch-point (34) for the discrimination of the exceeding or falling below of a specific actuation period of time which, in the event of not more than one hour's deviation from the items of time information (14) received by radio, in response to brief push-button actuation only temporarily clears the display device (18), but not its time store (35) stepped-on from the internal timekeeping circuit (16), but in response to lengthy pushbutton actuation gives rise to a complete system reset (26) into the operational initial position of the entire circuit system including its processor program forthe time evaluation.

4. A radio-controlled clock according to claim 3, characterised in that it is equipped with a multifunction switching device (21) with several pushbuttons (22), one of which is the reset push- button (22.2), by way of which the clock (11) can also be switched into a current-saving storage state and back out of this again for the start-up of the clock (11).

5. A radio-controlled clock according to claim 4, characterised in that upon its start-up in the display device (18) initially the items of time information stepped-on from the internal timekeeping circuit (16) are displayed, whereupon the display (18) switches over to a special region (29) for the presentation of the first items of time information (14) ascertained by radio, upon confirmation of which by subsequent items of time information (14) ascertained by radio the time display is handed over into the region of the display device (18) provided for this.

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