DE19631579A1 - Acoustic emergency shutdown apparatus for machines - Google Patents

Abstract

The apparatus includes a microphone (10) which converts the acoustic signal for an emergency shutdown into an electrical signal. The analogue signal is converted to a digital signal using an A-D converter (11). A processor (12) filters the signal and compares the signal with a selection of stop commands. If the signal is recognised as a stop signal the machine is stopped by breaking the emergency shutdown loop (14) using a relays (13). After the stopping the machine can be used again without affecting the operation.

Description

Technical field

The invention relates to protective devices for machines, in particular protective devices that keep the machine in Stop dangerous situations (emergency stop) or switch off (Emergency stop switch).

Technology Background

An emergency stop device for machines is for example in Europe prescribed according to EN 292. So far, such emergency stops Facilities usually have easily accessible and specially marked buttons triggered. But there will be also other mechanically triggered emergency stop devices used.

The recognition of language as required by this invention is no more problem. There are e.g. B. already toy cars and alarm clocks that spoken about Commands can be controlled.

problem

The existing emergency stop facilities all have the disadvantage that between the perception of the dangerous situation and the Actuation of the mechanical emergency stop device relatively much Time goes by. In a dangerous situation in which the staff itself, the machine or a workpiece is in danger the operating personnel first orient themselves before the conscious Triggering the emergency stop facility is possible. In some In some cases, it is not even possible for the operating personnel Trigger emergency stop.  

Experience shows, however, that the operating personnel are direct when recognizing the dangerous situation with reflex actions responds that could be used to trigger.

solution

The invention uses to trigger the emergency stop or emergency Off mechanism the verbal exclamation of the operator, the first when such a stress situation occurs is expelled. The most common exclamation in the event of impending dangers is "Stop" or "Halt". Is the workpiece already damaged? happens, it is usually reacted with swear words. If the operator has already been caught by the machine and can no longer reach the emergency stop, then it will be safe responded with cries for help or cries of pain.

Achieved advantages

The advantages achieved with the invention are that the verbal exclamation of the operating personnel, the one with appearance a dangerous situation is emitted, already to stop of the machine. This way you can usually already before a hazard or major damage occurs be reacted to.

In addition, the acoustic emergency stop or emergency stop Machine can be stopped even if that Operating personnel are no longer able to handle the mechanical Reach emergency stop facility.

execution

A possible embodiment of the emergency stop or emergency stop device ( 10 ) is described in more detail below.

The attached drawing shows

Fig. 1 shows a basic circuit of an emergency stop device. Microphone ( 10 ) for converting the acoustic signal into an electrical signal, analog / digital converter ( 11 ) for converting the analog signal into a digital signal, processor ( 12 ) for evaluating the signal and recognizing the command, relay ( 13 ) for Interrupt the emergency stop loop ( 14 ).

Explanation of the drawing

Fig. 1 shows a basic circuit of an emergency stop device. The acoustic signal (call of the operating personnel) is converted into an electrical signal via the microphone ( 10 ). This analog signal is converted into a digital signal via an analog / digital converter ( 11 ). A processor ( 12 ) filters the signal and compares it with the selection of the possible stop commands. If the collected acoustic signal is sufficiently similar to the comparison signals, the machine is stopped. For this purpose, the emergency stop loop ( 14 ) is interrupted by means of a relay ( 13 ).

The microphone ( 10 ) for receiving the call to stop the machine should be placed as close as possible to the operating personnel, since it is otherwise conceivable that the machine will already be stopped by a call at another work station. The microphone can therefore also be designed as a wireless tie microphone.

Because the noise level around a machine is usually relative is high, the signals can be filtered additionally. To digital filtering can be used.

Since only single words or exclamations have to be recognized, the effort of the circuit for detection is very low. In principle, the detection with conventional logic or can also be realized with fuzzy logic.

Since the operating personnel focus on the functioning of the Leaving facility, it is important that a non-radio the device for switching off the machine leads. Various control mechanisms are installed for this, which recognize, among other things, a missing microphone signal. A missing microphone signal is recognized, for example, by the ever-present background noise level suddenly disappears.  

When starting up the machine or changing the Operating personnel should have a short test (microphone sample) Ensure the function of the facility.

The comparison values to identify the exclamation at Stopping the machine does not have to be firmly integrated. In In a teach-in mode, electronics can find new terms be taught.

There is a possibility that the machine accidentally is stopped, so instead of interrupting the emergency stop loop a controlled stop (emergency stop) so that the machine after stopping without further notice Loss of time can be started again. That again starting after stopping must not be triggered acoustically machine, otherwise there is a risk to start unintentionally.

It is conceivable to use terms such as "Halt" or "Stop" assign good-natured stopping (emergency stop) to the machine while with cries like "help" or pain cries immediate stop (emergency stop) is triggered.

Instead of an exclamation of the operator, striking ones can also be used Noises from the machine, such as a break off of the Tool to stop the machine. It is also the case with machines that are always the same Work through processes, possible, the absence of acoustic Use procedures to trigger the facility.

To increase the general safety of machines, should the acoustic emergency stop device in addition to the conventional devices can be used.

Claims (9)

1. Emergency stop or emergency stop device for stopping or switching off machines, characterized in that the process for stopping or switching off the machine is triggered acoustically. 2. Device according to claim 1, characterized, that the process is triggered by a spoken command becomes. 3. Device according to claim 1 or 2, characterized, that the machine after the stop process (emergency stop) without Impairment of the interrupted work process again can be put into operation. 4. Device according to one of claims 1 to 3, characterized, that the facility complements the normal emergency stop on directions is used. 5. Device according to one of claims 1 to 4, characterized, that the establishment between commands for the good-natured Stop (emergency stop) and immediate shutdown (emergency stop) differs. 6. Device according to one of claims 1 to 5, characterized, that the facility retrofitted to existing machines can be grown. 7. Device according to one of claims 1 to 6, characterized, that the device sends the acoustic signals over a wireless microphone.   8. Device according to one of claims 1 to 7, characterized, that the machine is inoperative is switched off. 9. Device according to one of claims 1 to 8, characterized, that stopping the machine by not acoustic processes is triggered.