DE3140809A1 - "CIRCUIT ARRANGEMENT FOR MONITORING PHOTOELECTRIC CONTROL SYSTEMS" - Google Patents

Description

Title of the invention

Circuit arrangement for monitoring photoelectric Control systems

Field of application of the invention

The invention relates to a circuit arrangement for monitoring photoelectric control systems, in particular high-speed stranding machines, with the control systems constantly monitor the position of the coil frames and the light barriers themselves and signal deviations from them.

Characteristics of the known technical solutions

Spool frames of high-speed stranding machines are easily rotatable in the axis of rotation of the stranding machine. They stay due to their low center of gravity in their normal position and only evade this if the bearing friction becomes greater than the restraint force. If this occurs, it is necessary to turn the stranding machine off as quickly as possible to bring to a standstill. It is therefore necessary to constantly monitor the position of the coil frame. The first Monitoring systems or disconnection devices were safety contacts arranged on the coil frame, which when the Coil frame interrupted the output circuit and let the unit brakes apply. These internal contacts Systems have a significant technical disadvantage, which is that the power line over Slip rings takes place. In order to avoid signal transmission by means of slip rings, one has switched to the

To monitor coil frames by light barrier systems. In the DD-PS Ir. 105 478 such a system is described, each of which consists of two bobbins arranged outside the rotor Various types of light sources are ventilated, the rays of which are directed through diaphragms at an angle to one another form and, going through the window openings of the Verseilrotors, directed directly or reflected on the photo receiver are. The pulses occurring during the rotation of the stranding rotor are fed to an electronic counter, the if a pulse train fails, a signal to switch off the Machine delivers.

In DD-PS No. 55 246, a light barrier system is also included described with only one light barrier per spool frame, but this system works without self-monitoring.

In addition, the system shown there is not always operationally reliable. The light barrier system according to DD-PS 105 478 is operationally safe by law, but still right laborious. Two light barriers are required for each coil frame. There are also expensive meters and building blocks for self-monitoring.

Object of the invention

The aim of the invention is to reduce the costs for that provided for coil frame monitoring while maintaining the same or increased safety To reduce the light barrier system.

Explain the essence of the invention

The object to be achieved by the invention consists in creating a circuit arrangement for monitoring photoelectric control systems, in particular on high-speed stranding machines, which is simple in construction and is operationally reliable, the circuit complexity for a number of light barrier systems not being significant is higher than the effort for a light barrier system.

The invention solves the problem by means of a circuit arrangement in which the outputs of any number of light barriers are simultaneously connected to the inputs of an AND gate and an OR gate and the output of this OR gate is connected to the output of the first-mentioned AND gate via an negator and another OR gate, the output of the last-mentioned OR gate via a further AND gate, a timing element and a self-holding loop forming AND and OR gate with a relay to switch off the drive circuit and to operate the Braking is connected, while the second input of the second AND gate is connected to the output of an equivalence gate is, one input with the first-mentioned OR gate and the second input with one of the rotor Stranding machine or its bracket is connected to the contactless scanning encoder.

In addition, the invention provides that in the case of tubeless and iron-free high-speed stranding machines, the contactless scanning encoder is replaced by a synchronously driven generator, which is connected to the input of the equivalence gate and in parallel via a delay element with the second AND gate and also in parallel with is electrically connected to the light barriers.
The invention also includes that the charging time constant of the delay element is significantly greater than the discharge time constant.

It belongs to the essence of the invention that instead of the Verseilrotors the transmission wave as a signal generator for the contactless scanning encoder is provided.

Embodiment

The invention is illustrated with reference to the drawing Embodiments explained in more detail. It means:

Pig. 1 shows a circuit arrangement for high-speed stranding machines with tubular! Rotor or with bracket

Pig. 2 a circuit arrangement for tubeless high-speed stranding machines.

In the circuit arrangement according to FIG. 1, all outputs are the light barriers 1 required according to the number of coil frames on the AND gate 2 and parallel to it the OR gate 3 led. The AND gate 2 is on the output side connected to the input of the OR gate j6, which in turn is connected to the AND gate 7. About the timer 8, AND gate 9 and OR gate 10, the connection goes to relay 11. Between AND gate 9 and OR gate 10 a self-holding loop is formed. The OR gate 10 is also connected to the acknowledgment element 14. The OR gate 3 has an equivalence gate on the output side 5 and connected to an inverter 4. The output of the latter is connected to the input of the OR gate 6. The inverter 5 is in turn connected to the input on the output side of the AND gate 7 and on the input side with an encoder 12 tied together. If the coil frames (not shown) are in their normal position, the beams from the light barriers 1 through the window of the Verseilrotors 13 directly or indirectly via a reflector belonging to the light barrier system for Get receiver. At the output of all of the light barriers 1 arranged on the stranding machine, high signals arise, so that A high signal likewise appears at the output of AND gate 2, which signal reaches AND gate 7 via OR gate 6. So that a high signal is generated at the output of AND gate 7 appears, the output of the equivalence gate 5 must have a high signal hand over. This is always the case when the inputs of gate 5 have the same level. There over the OR gate 3 A high signal appears, the signal from the contactless encoder 12 must also have a high level. Depending on the type of Encoder 12 is the negated or non-negated output here to use. The contactless transmitter 12 is intended to scan the openings in the twisting tube. As a result of the wire guides on the stranding tube 13 the encoder 12 is arranged at the front and scans the stranding tube openings over equivalent segments « If a light barrier 1 fails so that the output emits a low signal, although rays hit the receiver, so receives the relay 11 via the AND gate 2 and the downstream Gates 6, 7, 8, 9, 10 a switching pulse. The circuit for the stranding machine drive is interrupted and the brakes are activated.

If the rays of the light barriers 1 through the stranding tube 13, that is, through his. Window bars or interrupted by the brackets of the wire feed, a low signal appears at the output of gates 2, 3. Since the transmitter 12 also emits a low signal at the same moment, a high level occurs at the output of the equivalence gate 5. Via the negator A , via the OR gate 6, the high signal reaches the second input of the AND gate 7. The high signal coming from the equivalence gate 5 is present at the first input. The relay 11 thus receives no switching pulse.

The circuit arrangement shown in FIG. 2 differs differs essentially from the circuit arrangement shown in Fig. 1 only in that the encoder 12 by a Generator 15 is replaced by a delay element 16 is maintained. The generator 15 takes over the function of the encoder 12 and also switches the light barriers 1 on and from. The generator 15 is activated by the delay element 16 monitored, in which the charging time constant is much larger than is the discharge time constant. The output of the delay element 16 is led to the negated input of the AND gate. Disturbances of the light barriers 1 such that when the beam is interrupted If the high level is retained at the output, the Stranding machine, d. H. an impermissible deflection of the coil frame is not registered.

The circuit arrangement at hand registers these faults via gates 3, 5. Via gates ^T , 8, 9, 10 and relay 11: the stranding machine drive is switched off and the brakes are applied. The timing element 8 (gate) suppresses unwanted switching peaks, gate 9 and gate 10 form a delbsfchalteschleife. If the input of the acknowledgment element 14 is briefly given a high signal, z. B. via a "Acknowledge error" button, the high signal is sent via gate 10 to relay 11. The latter releases the brake and unlocks the stranding machine drive. If, however, a low signal appears at the input of gate 9 coming from timing element 6, then the relay drops out via gates 9, 10 and also remains

* »« ■ -I * t * ί

with a recurring high signal switched off until the error is acknowledged at the acknowledgment element 14.

fusing of the reference symbols used

1 - photocells

2 - AND gate

3 - OR gate

4 - kegator

5 - equivalence gate

6 - Qder gate

7 - AND gate

8 - timer

9 - AND gate

10-OR gate

11 - relay

12 - contactless encoder

13 - Stranding rotor H acknowledgment element

15 - generator

16 - delay element

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Claims (4)

Invention claim /1. Circuit arrangement for monitoring photoelectric control systems, especially on stranding machines that run fast, with the control systems constantly changing the position monitor the coil frame and signal deviations from the same, characterized in that the outputs the light barriers monitoring the coil frames (1) are simultaneously electrically connected to the inputs of an AND gate (2) and an OR gate (3) and the Output of the OR gate (3) via an inverter (4) and another OR gate (6) with an output of the AND gate (2) is connected, the output of the OR gate (6) via an AND gate (7) a timing element (8) and via the AND gate (9) and OR gate (10), which form a self-holding loop, with a relay (11) is connected, while the second input of the AND gate (7) is connected to the output of an equivalence gate (5) is whose one input with the. OR gate (3) and its second input with a stranding rotor (13) or whose bracket is connected to the contactless scanning encoder (12). 2. Circuit arrangement according to item 1, characterized in that that in the case of tubeless and iron-free high-speed stranding machines, the contactless scanning encoder (12) by a generator (15) is replaced, on the one hand with the input of the equivalence gate (5) and in parallel via a delay element (16) is connected to the AND gate (7) and still in parallel with the light barriers (1). 3. Circuit arrangement according to item 1, characterized in that that the charging time constant of the delay element (16) is significantly greater than the discharge time constant. 4. Circuit arrangement according to item 1, characterized in that that instead of the stranding rotor (13), the transmission shaft is provided as a signal generator for the transmitter (12).