DE2755665A1 - APPROXIMATE LOCATOR - Google Patents

Description

Proximity locator

The invention relates to a proximity switch assembly, and particularly relates to ultrasonic reflective technology.

Such devices are known, but on the one hand they are quite complex and therefore costly to manufacture will, on the other hand, show a very unreliable mode of operation in practice.

The invention is therefore based on the object of a method for proximity location and a device for implementation of the process that are inexpensive to manufacture and are extremely reliable.

This object is achieved according to the invention by the in the characterizing Part of claim 1 or claim 2 and the features specified in the claim solved. Further features of the invention are specified in the subclaims.

Exemplary embodiments of the invention are shown in the drawing and are described in more detail below. It shows

FIG. 1 is a schematic representation of an ultrasonic proximity locating device;

Figure 2 is a graphical representation of the signal or waveform of the used Signals in the facility;

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FIG. 3 shows the device according to FIG. 1 in use for controlling a sanitary Water outlet device.

The locating device shown in FIGS. 1 and 2 contains an oscillator 11, which has a first gate circuit

13 is coupled to an electroacoustic transducer 12, wherein the transducer is designed so that it can generate and receive acoustic signals. A second gate circuit 14 couples the converter 12 via an amplifier 15 tuned to the frequency of the oscillator 11 to a level or Threshold detector circuit 16 and a velocity sensor circuit 17 (velocity sensor circuit), both circuits 17 and 16 being connected in parallel. The gates 13 and 14 are thereby by one Gating generator or control device 18 is controlled.

The gating generator feeds a stream of pulses Fl (Fig. 2) into the first gate circuit 13 and couples the oscillator 11 to the converter 12 for the duration of each pulse, whereby the converter 12 is excited to a corresponding intermittent ultrasonic radiation according to F2. In the period between each Beam burst, i.e. the gate circuit 13 is closed, the gate circuit 14 is opened by an extended pulse F3, and during this period the transducer works as a receiver. The duration and time of the extended pulse F3 determines the operating range of the proximity locator, i.e. an echo pulse can only be received during the "receive window" defined by the pulse F3.

Echo signals F4, which are received by an object 19 during the pulse F3, generate a corresponding electrical signal Signal in the converter 12, which via the gate circuit

14 is fed into the tuned amplifier 15. The exit the amplifier is equipped with a threshold detector circuit

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coupled, in which an output signal is generated when the amplifier output exceeds a predetermined amplitude. This facility defines the facility's area of activity. With a suitable adjustment device the gating generator or control device 18, the device can be adapted to the particular circumstances of the field of application and unwanted echo signals from more distant objects are switched off.

In some areas of application it may also be necessary to use the device to determine a movement of an object and / or measure. In this case, a motion detector circuit 17 is in parallel with the threshold detector circuit 16 switched. This circuit measures and determines the time intervals between the continuous echo pulses F4 Speed of the object 19 from the Doppler shift to the basic frequency.

In Figure 3 of the drawing, the proximity locating device is shown together with a water outlet device, the water outflow contactlessly by the ultrasonic control device is operated, as is required, for example, for operating rooms in hospitals. The outlet fitting 31 is provided with a solenoid valve 32 which is actuated via a relay or an amplifier 33. The control device 18 is designed so that the "received signal window" corresponds to a predetermined maximum Distance, for example 1 meter, between the tap and a user. If the user is within this Area, the reflected ultrasonic signals received by the device and converted into an output signal, which opens the solenoid valve 32 with the aid of a relay or an amplifier 33. The user moves away from the outlet fitting 31 over the predetermined distance, the reflected ultrasonic signals are no longer received and the solenoid valve closes the water outlet,

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Further areas of application of the proximity locating device according to the invention are for example in oil and water tank systems, burglar alarm systems, automatic door openers or as a safety device for vehicle crude oil pumps to prevent petroleum leakage when the pump is running is unattended.

ORIGINAL INSPECTED

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Claims (5)

DITTI 176 K.E. Bearcroft - 4 REQUIREMENTS 1.) Proximity Ortungselnrichtung, characterized in that "a transducer (12) acting as a transmitter and receiver a first gate circuit (13) with an oscillator (11) and via a second gate circuit (14) with a demodulation circuit is coupled and that a control device (18) is provided for the selective operation of the two gate circuits 1st, in such a way that the transducer is intermittently brought to radiation and the demodulation circuit for a predetermined Part of the period between each transmission is coupled to the transducer. 2. Device for controlling the water flow in wash basins or the like, wherein the water flow is directed via an electrically operated valve and the user is detected by a proximity switch, characterized in that, that an ultrasonic transducer acting as a transmitter and receiver via a first gate circuit is used to control the flow is coupled to an oscillator and via a second gate circuit to a demodulation circuit and that a control device is provided for the selective operation of the two gate circuits, in such a way that the transducer is excited to generate radiation in a pulsating manner and the demodulation circuit is coupled to the transducer for a specified portion of the period between each transmission, the device is designed so that when an echo signal is received from the transducer, the valve (32) is opened and Water can flow out. 809826 / 06S3 3. Device according to claim 1, characterized in that Means are provided for measuring the time interval between the continuously transmitted signals and the echo signals so that the speed of the detected object can be determined. 4. Device according to claims 1 to 3, characterized in that that the output signal of the proximity locating device is a relay or an amplifier (33) for actuation of the solenoid valve (32) in the drain fitting (31) controls. 5. Procedure for operating an automatic water outlet fitting, characterized in that ultrasonic wave pulses (F2) are emitted briefly at periodic intervals and are reflected by objects in the radiation area, the pulse-shaped echo signals (F4) from one between the transmission periods, adjustable in its reception duration (F3) receiver are included and the outlet fitting steer. 8098 26 / 0- ':'