DE2515277C2 - Sequential control device to be operated pneumatically - Google Patents

Description

60

The invention relates to one pneumatically Sequential control device to be operated, which has a switching element and adjustable with a stepping motor has a ring of catching nozzles assigned to it, and depending on the pressure signal leaving the long nozzle to which it is applied, via a with Compressed air from the outside acted upon AND element an output signal is generated that a working movement triggers at the end of a feedback signal Acknowledgment signal is generated, which is used to control the stepper motor for the switching element

In the magazine "Fluid Power International", 1970 p. 29-32, there is already a sequence control with the above enumerated features described, which can only be operated with high pressure air and right is complicated and in which, above all, an interference of functions in the area of each circuit is easily possible

In contrast, the invention is based on the object of a pneumatically-fluidically operated, To create series-produced sequential control device of the type in question here, the small one Has structural dimensions and with a simple structure and relatively low initial costs and simpler Operation is applicable in the widest range of areas

For the above purpose it is provided according to the invention in the new sequence control device that the Switching from one catching nozzle to the next Catching nozzle takes place in two half-steps and that the pressure signal leaving each loaded catching nozzle is a second AND element can be supplied. which receives the feedback signal as a further signal and its Output is connected via a multiple OR gate to which the signal line carrying the acknowledgment signal and establishing the connection to the stepper motor is connected. the first half step by the incoming acknowledgment signal and the second half step by the Loss of the pressure signal at the relevant catching nozzle and thus the acknowledgment signal after the first one Half step is triggered.

The sequence control device according to the invention can optionally be operated with high or low pressure air In addition, it has a relatively simple structure, is more compact and less space-consuming. before but above all it is very reliable in operation, because of that the division of the SchcUschrvf into two each Half steps an interference of functions is avoided. At the same time arise with the new Sequence control device Expansion options that make the area of application appear practically unlimited. So is the new sequencer Can be used as a sequence control, for selecting coordinates in palletizing devices. in special control devices as a superordinate or subordinate unit, etc. The new sequential control device can be installed in a machine base because of its small dimensions or installed in other existing housings, but it can also be installed in its own housing be organized. For the connection with the devices to be controlled, for example a cylinder, a Valve or a pneumatic switch, only two hose connections are required, namely one Feed tube and a signal tube. As a result of the built-in feedback display, possible Errors are easily found: if the sequencer inadvertently triggers a remains in a certain step, there is either a missing confirmation display, for example Failure in the pneumatic supply line. or a connection hose is torn, or there is one The end position has not been reached, or a limit switch provided in a device to be controlled is defective, or there is a fault in the sequencer. The faults can also be caused by the operator

personnel can be easily identified even without special specialist knowledge. Other advantages of the Invention consist in the fact that it has an often required ease of use, such. B. gradually Operation for setting up, control of any program steps in any order Display of the step number, automatic counting of the cycles and visual display of the incoming feedback are built in as standard.

Di * · invention is described below with reference to the in Drawings schematically illustrated embodiment explained in more detail

F i g. 1 shows a sequence control device according to the invention in a schematic representation, while FIG. 2 an additional circuit to the device according to FIG. 1 also shows schematically.

Using the sequence control device according to FIG. 1, the generation of the step and output signals as well as the selection and summary of the feedback is shown. The stepping motor 10, which has an adjustable switching element, to which a ring of catching nozzles is assigned, gives in absenti! of an advance command Q _g , = 1 on one output signal line and only one output signal line from a "1" signal (in the present case on line 0). In the presence of an advance command, a "1" signal is not given to any connection. The output signal 0 arrives at an amplifier represented as an AND gate 11 (double AND gate) (e.g. identity element for output signals in the low-pressure area, or 0.1-6 bar amplifier for high-pressure outputs), which is supplied via the internal (and therefore marked by a black arrow) connection P *. is fed. If there is a power supply, a corresponding signal of 0.1 or 6 bar appears at the external (and therefore marked with a white arrow) output A 0.

From the output signal line 0 of the stepping motor 10, a junction 12 leads to a triple AND gate 13. Its second input receives from one internal connection provides a start signal if necessary QOa = I, while the feedback QO from the corresponding external connection to the 3rd input of said AND gate 13 is supplied.

The output of the triple UN D gate 13 is connected to the 12-way OR gate 15 via the line 14.

In the presence of a feedback signal QQ = \. which indicates the successful completion of the operation triggered by the output signal A 0, leads a start signal O0a = 1 via the 12-fold OR gate 15 to generate the general acknowledgment Qg = X. If one imagines a connection from the internal output Q _g - the display or acknowledgment line - to the internal input Q _g , a "!" Output signal puts the bellows 16 of the stepper motor 10 under pressure and thereby causes a first half step. The "!" Signal on line 0 disappears, and at the same time / 4 0 = 0, without another output line of the stepping Sulimotor 10 or another external output of the sequential control device emitting a "!" Signal. This also makes Q ₁ = O. which relieves the bellows and thus also leads to the execution of the 2nd half-step. The stepping motor 10 is now on position 1 (which, by the way, can also be read on the unit wheel of the step switch 10) and sends a "1" signal to output line 1. If P * is supplied, output Λ 1 becomes active, and via AND- Γ. , · The confirmation Q 1 is selected. As soon as Ql = H, Qq = X also occurs, and in the sense of the connection Q ₁ .- Q _gs mentioned above, the next step is initiated at position ζ . All further steps are carried out in the same way until the rest position 0 is restored. It should only be mentioned that when the transition from step 9 to step 0 in the counter part, which serves as the basis for the stepping motor 10, a tens transfer takes place

ίο Cycles possible, for which 5 decimals are available stand

In Fig. 2 a simple additional circuit is shown, which the sequence control device shown in Fig. 1 for the purpose of achieving an often desired operating and added service convenience.

The general feedback signal Q _g is initially fed to a display and an AND gate 17, the second input of which comes from an OR gate 18 which has a key signal “step / step permission / start” = 1 and / or a switch signal “automatic” = 1 forwards The output signal of the aforementioned AND gate 17 is fed to a further WD gate 19 on the one hand, but is on the other hand at the external output Sub for special purposes (e.g. triggering a repeated, possibly controlled by subroutine-controlled operation) Disposal. Another external connection O ₅ leads to the second input of the last-mentioned AND gate 19, the output O * _{5 of which is} internally connected to the bellows 16 of the stepping motor 10.

The elements of the additional circuit described above work as follows:

Activation:

EIN enables output signals to be given and makes progress from presence dependent on the corresponding feedback (see also »Automatic«): OFF blocks the output of output signals and allows you to advance by pressing a button,

if the corresponding feedback is not available.

Automatic:

ON enables the fully automatic program sequence from step 1 up to and including 9 if Repetition switched off and enables the repeated, fully automatic program sequence with automatic or externally controlled start from step 0 (= rest step) to and

with 9 if repetition is switched on;

OFF allows switching to the next only as long as the button is pressed («tip mode].

Repetition:

OFF allows the button to function as a start button when the automatic system is switched on and activated, but the corresponding feedback Q ₀ must be present; EIN only makes the start dependent on the presence of the relaxing feedback Oo

gig (external start command or repetitive function).

Step (permission) / start

The key causes half-step wciscs to continue

ECi..ilien fall 'Activation switched off!. In In all other cases, the button can only give permission to continue sounding in the sense of

Hand in tip operation. In the case of a non-automatic program sequence, the button should only be used briefly not to be printed out in the event of a response that is received quickly or that has already been received to take more than one additional step.

Feedback (display in key):

The presence of the feedback 1 up to and including 9 is always displayed. Feedback becomes 0 only displayed if repetition is switched on or key is pressed while activation is switched on is.

With the help of the key further signals are generated: via an inhibitor (only open if the activation is not switched on!) A signal Y from 12-fold OR can be given via an internal connection. Furthermore, the £ fy / ühriic Sϊ ?, RisiTi2! * ~ * Qs —1 srzc «"! "'Srdsri, if you don't prefer to use the» Repetition «button to enable the start continuously. The last thing to be mentioned is the »Activation« switch, which on the one hand prevents the E'T / ciung of the signal Y - I and thus the simulation of the general feedback Q _f when switched on and on the other hand the supply for the output elements via an AND- Releases the element shown in the gate. It goes without saying that a pressure level corresponding to the selected pressure level (.I or 6 bar); Switching element (as in the case of the output amplifier) to be used.

Regardless of whether the sequential control device may be together with further extensions in a 19 "housing. used in a special housing (e.g. also machine base!) or more or less openly the connection is made via two 22-way multi-pin plug, but which do not have to be fully populated. Since all occupied but unused connections are closed must be, the Mullipol connector must be equipped with sockets at least as far as occupied Connections are available.

For this purpose 2 sheets of drawings

Claims (5)

Patent claims: 1. Sequential control device to be operated pneumatically, which has an adjustable switching element and a step servomotor has this associated catching nozzle ring, depending on the pressure signal leaving the respective activated catching nozzle via an externally pressurized to AND element with compressed air generates an output signal that triggers a work movement, at the end of which an acknowledgment signal is generated by a feedback signal which is used to control the stepping motor for the switching element, thereby marked π draws that switching from one Catching nozzle to the next catching nozzle takes place in two half steps and that each acted upon The pressure signal leaving the catch nozzle can be fed to a second AND element (11), which acts as a further signal the male dog receives the eldesignal and its output via a multiple OR gate (15) with which the Acknowledgment signal carrying the connection to the stepping motor (10) establishing the signal line connected is. the first half-step through the incoming acknowledgment signal and the second half-step through the elimination of d / »s pressure signal at the actuating catching nozzle and thus the acknowledgment signal is triggered after the first half-step has taken place. 2. Sequence control device according to claim 1, characterized in that the with the catch nozzle AND element (13) interacting in the catching ring is designed as a triple AND gate, whose third input is connected to a start signal line, and that the other Second AND elements (11) assigned to catch nozzles are each designed as a double AND gate. 3. sequential control device according to claim I or 2, characterized in that a bellows (16) is used to drive the stepping motor (10). 4. Sequence control device according to one of claims I to 3, characterized in that when "/?" Catching nozzles the outputs of the second AND elements (11) are connected to the inputs of an "n + 2" -fold OR gate (15), the output of which is connected to the Acknowledgment line is connected 5. Sequence control device according to one of claims 1 to 4, characterized in that the general feedback is an AND gate (17), the second input of which comes from an OR gate (18) and the output signal on the one hand an external terminal (Sub ) a control for special purposes, and on the other hand a further AND gate (19), whose / further input is connected to a further external connection (?, and whose output (Q ₁ ,) is internally connected to the bellows (16) of the sequential control device is.