EP0524424B1 - Method of operating a portable transmitter to drive vehicle functions - Google Patents

Description

The invention relates to a method for operating a handheld transmitter for controlling vehicle functions with the features of the preamble of patent claim 1.

A method with these features can be derived from the mode of operation of an infrared hand-held transmitter supplied for remote control of functions in vehicles manufactured by the applicant.

The output signals that can be emitted by this hand transmitter essentially consist of a code component and a maintenance component. With the code portion, a relatively short coded message is transmitted from the transmitter to a vehicle-mounted receiver in a known manner, which enables z. B. to activate a central locking in the unlocking or locking direction or even from a greater distance from the vehicle. The maintenance component, which in the vehicles equipped with a convenience lock also enables the closing of windows and the sunroof that are still open after leaving the vehicle, is only emitted for as long as the transmit button on the handheld transmitter is continuously longer than a predetermined period of time is recorded immediately after the radiation of the locking code signal, so only for the desired duration the window or sunroof closing movement. For security reasons, the latter only sets after a certain period of time, e.g. B. 0.25 sec after the start or after receiving the maintenance signal on the vehicle, as well as the need to hold the transmit button already represents a security measure.
In the simplest case, the maintenance component consists of repeated clock pulses, which are transmitted at constant intervals with the intensity or signal level unchanged compared to the code signal. The output power of the handheld transmitter and its range thus remain the same (see Fig. 2).
In view of increased efforts to ensure the operational safety of vehicles, in particular also with such convenience locking systems, it is desirable to be able to operate the latter by means of a remote control hand transmitter only in a relatively narrow spatial area around the vehicle.

The characterizing features of method claim 1 indicate an inventive solution to this problem.
In this solution it is e.g. B. irrelevant whether the output signal for controlling the convenience closing drives z. B. is activated via a separate key of the handheld transmitter following a previous actuation of a code signal transmission key, or whether only a single transmission key is provided. In the former case, the receivable output power can be determined simply by selecting the button.

A hand-held transmitter is known (DE 38 06 130 A1), the output power of which is variable depending on the strength of the ambient light.

The features of the subclaims reveal advantageous developments of the method according to the invention. After subclaim 2, the receivable output power of the hand-held transmitter and thus its range is automatically reduced during the course of the successive output signals which can be activated by a single transmission button in accordance with the prior art discussed above.

One possibility is to reduce the electrical output power of a signal source in one stage by connecting a resistor - which forms an electrical folder.

Another possibility is to provide two signal sources next to each other in the same handheld transmitter, one of which can emit unfiltered or unimpaired at full power, the other can only emit through a filter upstream or with reduced power. In this embodiment, an automatic, for. B. time-dependent controllable switch for switching from one signal source to the other.

Another possibility with two signal sources can be realized by activating them together for a long range and switching off one of them to reduce the range.

Finally, within the scope of the inventive concept, dialog control of the receivable output power of the hand-held transmitter is possible as a function of a switching signal with a long range that is transmitted by the vehicle even after complete reception of a suitable code signal and can be received and evaluated in the hand-held transmitter.

Possibly. suitable variable signal filtering could also be provided, e.g. B. by switching on a suitable depending on the signal carrier type (infrared, ultrasound, radio) selected Filters in front of the signal output during the emission of the output signals controlling the drives.

A sketch of the possible signal sequence in the operating mode of the handheld transmitter according to the invention and exemplary embodiments for handheld transmitters are shown in the drawing and are described briefly below.

Figur 1

einen Signalverlauf eines Handsenders über der Betätigungszeitdauer seiner Sendetaste gemäß dem erfindungsgemäßen Verfahren,

Figur 2

einen entsprechenden Signalverlauf gemäß dem Stand der Technik,

Figur 3

einen Handsender mit zwei Signalquellen, die mittels eines steuerbaren Schaltglieds wechselweise zum Abstrahlen von Signalen einschaltbar sind,

Figur 4

eine Skizze mit einer Infrarot-Signalquelle, der von einem steuerbaren Schaltglied ein leistungsmindernder Widerstand vorschaltbar ist,

Figur 5

eine Skizze eines Dialogsystems, in dem die empfangbare Ausgangsleistung eines Handsenders (Transponders) im Dialog mit einem fahrzeugfesten Sender (Transponder) steuerbar ist.

Show it

Figure 1

a signal curve of a hand transmitter over the actuation period of its transmit button according to the inventive method,

Figure 2

a corresponding signal curve according to the prior art,

Figure 3

a hand-held transmitter with two signal sources, which can be switched on and off alternately to emit signals by means of a controllable switching element,

Figure 4

1 shows a sketch with an infrared signal source, which can be connected upstream of a controllable switching element with a power-reducing resistor,

Figure 5

a sketch of a dialog system in which the receivable output power of a handheld transmitter (transponder) can be controlled in dialog with a vehicle-mounted transmitter (transponder).

In both diagrams according to FIGS. 1 and 2 , the receivable output transmission power p of a hand-held transmitter - which corresponds to its range - is plotted in a highly schematic manner over a time axis t when a transmit button is pressed continuously.

The signal sequence begins when the send button is pressed. The abbreviations ZV / EDW and KB stand for locking devices or control elements of a central locking system / burglary-theft alarm system or for drives for comfort controls.

It can be seen from FIG. 2 that in the known signal curve the successive pulses of the code component C (control of the vehicle functions ZV / EDW) and the maintenance component A (control of the vehicle function KB) have the same amplitudes P. A dashed vertical line below the time axis in the area of maintenance portion A indicates that control of the comfort controls KB (drives for window lifters, sunroof, seat adjustment) is only possible after a delay. This would correspond to the fact that in the case of a transmitter with two transmit buttons for the different signal types C and A, the choice of the button has no influence on the amplitude and range.

FIG. 1 , on the other hand, shows that, according to the method according to the invention, with a constant waveform with respect to the pulse train, the amplitude of the pulses of the maintenance component A is significantly, approximately 50%, less than the amplitude of the pulses of the code component C.

This significantly reduces the receivable output power of the handheld transmitter and its range for the convenience function (KB) compared to the relatively long range for the locking (ZV) and anti-theft function (EDW). For a transmitter with two transmit buttons, the full output power or range would be available with the button for signal type C and the reduced output power with the button for signal type A.

It is understood that other methods for influencing or reducing the actual output power can be used within the scope of the invention, e.g. B. pulse width control.

FIG. 3 shows a partially cut-open view of a hand transmitter 1 for infrared rays, which can be activated manually using a single transmission button 2. In addition to the usual storage, coding and energy supply means not shown, it includes an automatically controllable switching element 3 with a changeover contact 4 and a first infrared transmitter diode 5 and a second infrared transmit diode 6 as a signal source, which can be controlled alternately via the changeover contact 4. The first infrared transmitter diode 5 is arranged behind a transparent cover 7 in the housing of the handheld transmitter 1, which does not significantly reduce or attenuate the transmit (light) power that can be emitted by the transmitter diode 5 and can be received by a downstream receiver.
In contrast, the second infrared transmitter diode 6 is arranged behind a cover 8 which is also transparent but absorbs part of the transmission power.
Therefore, even with identical design and power consumption of the two signal sources or transmitter diodes 5 and 6, the transmit power emitted by the latter can only be received in a weakened manner by a downstream receiver.
Correspondingly, the automatically controllable switching element 3 will switch its changeover contact to the transmitter diode 6 if and only after the radiation of the code signal or portion marked in FIG. 1, the power / range-reduced maintenance signal is to be emitted.
This process can be controlled by the program sequence of the hand-held transmitter on the software side or purely time-dependent via a timer (timer, clock), because with the present transmitter type the time extension of the code signal to be emitted and thus the time period between the start of the transmission button 2 and the time of the range switch is always constant.

The same applies to an automatically controllable switching element 3 'according to FIG. 4 , which can connect a series resistor 8' to a single transmitter diode 5 'of a hand-held transmitter, not shown, which then limits the power consumption of the transmitter diode 5' compared to the basic position shown and thus also to be regarded as a filter for the receivable output power.

Analogously to this design, it would also be possible to provide two transmitter diodes 5 and 6 as in FIG. 3, but to let them emit unfiltered and normally - for the code portion - together, but to switch off one of them by means of the automatically controllable switching element in order to reduce the receivable output power . This also reduces the power consumption of the overall signal source and its range.

Finally, an arrangement is sketched in a greatly simplified manner in FIG. 5 , in which an automatically controllable switching element 3 ″ of a hand-held transmitter 1 ′ - as shown in FIGS. 3 and 4 - can be activated in dialogue with a vehicle-mounted transmitter with a long range.

A vehicle F is only partially indicated here as a dashed frame. A vehicle-mounted receiver 9 with a downstream control device 10 and a transmitter 11 controllable by the latter are arranged therein. The control unit 10 also masters the vehicle functions ZV / EDW and KB, which have already been mentioned several times, as indicated schematically here by function blocks. A hand-held transmitter 1 'indicated to the left of the vehicle in turn comprises a signal source 5''whose receivable output power in a suitable manner - as shown above - can be changed via the automatically controllable switching element 3 ″ in the sense of the sequence in FIG. 1. In addition to the signal source 5 ″, a receiver 12 is now also provided in the hand transmitter 1 ′, which receives the signals that can be emitted by the transmitter 11 fixed in the vehicle.

This arrangement is now operated in such a way that when the handheld transmitter 1 'is activated, the signal source 5' 'emits a code signal to the vehicle-mounted receiver 9 by means of its transmission button (not shown here). This is decoded in the control unit 10 in the usual way and converted into a control command directed to the ZV / EDW function. At the same time, the control unit activates the vehicle-mounted transmitter 11 after receiving a complete code signal - which of course must match the code stored on the vehicle side. Its long-range signal is sent to the receiver 12 of the handheld transmitter 1 ', which then activates the switching element 3' '(for the Duration of actuation of the send button). This then reduces the receivable output power of the signal source 5 ″ and thus its range in the manner previously discussed.

In this arrangement, both the handheld transmitter 1 'and the transmitter-receiver combination in the vehicle F have a transponder function.

It is understood that the exemplary embodiments shown can also be carried out with transmission media other than infrared waves without departing from the basic concept of the invention.

Claims (7)

1. Method for operating a hand-held transmitter (1,1') for controlling vehicle functions, the hand-held transmitter being able to emit output signals (A, C) for controlling both locking devices and drives, especially sliding roof and window drives, for closing vehicle openings, characterised in that the output signals (A) for controlling the drives are emitted with a lower output power and range than the output signals (C) for controlling the locking devices.
2. Method according to Claim 1, in which the hand-held transmitter emits contiguous output signals, when a transmitting key is operated continuously, with a leading code section of limited time duration for controlling the locking devices, and a subsequent maintenance section for controlling the drives, characterised in that the output power which can be received from the transmitter is automatically reduced by switching means once the code section has been emitted.
3. Method according to Claim 2, characterised in that the amplitude of pulses in the maintenance section is reduced compared with the amplitude of pulses in the code section.
4. Method according to Claim 1 or 2, characterised in that the power consumption of a signal source (5'), and hence its output power which can be received, is reduced once the code section has been emitted.
5. Method according to Claim 2 or 4, characterised in that, once the code section has been emitted, a change-over is made, by means of a switching element (3; 3'; 3''), which can be controlled automatically, from a first signal source (5) of the hand-held transmitter (1) to a second signal source (6) of the hand-held transmitter, in order to reduce the output power which can be received.
6. Method according to Claim 2 or 4 or 5, characterised in that the output power which can be received from the hand-held transmitter can be controlled in a dialogue with a transmitter which is fixed to the vehicle, in that, once the output signals for controlling the locking devices have been received at the vehicle end, the transmitter which is fixed to the vehicle emits a long-range changeover signal, which can be received by the hand-held transmitter, that is provided with a receiver, and can be evaluated by a changeover device, which is inside the transmitter and can be controlled automatically, in order temporarily to reduce the transmitted power which can be received from the hand-held transmitter.
7. Method according to Claim 1 or 2, characterised in that, during the emission of the output signals controlling the drives, a suitable filter is switched on, which is selected depending on the type of signal carrier (infrared, ultrasound, radio).

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