DE112013002197B4 - Means for supplying a negative pressure consumer of a sheet-processing machine in a working cycle of the sheet-processing machine with negative pressure - Google Patents

Abstract

Device for supplying a vacuum consumer of a sheet-processing machine in a working cycle of the sheet-processing machine with negative pressure, wherein by a control unit between a air pressure source and an ejector (3, 3 ', 3'') arranged first valve (2, 2', 2 '') openable and closable controllable during each work cycle and an inlet of small cross-section of the ejector (3, 3 ', 3'') can be acted upon with an overpressure air flow of the air pressure source, by the ejector (3, 3', 3 '' ) to an atmosphere leading to the outlet (5), wherein between the inlet (4) and the outlet (5) of the ejector (3, 3 ', 3'') a radial port (6) in the ejector (3, 3 ', 3'') leads, which leads via a suction line to the vacuum consumer, characterized in that the sheet-processing machine with several different work cycles per unit time is operable and in a memory (13) of a control unit (1) s several different opening times (14) and respectively associated closing times (15) of the first valve (2, 2 ', 2'',2''') are stored as a function of a plurality of different numbers of work cycles per time unit and of the control unit (1) the first valve (2, 2 ', 2'',2''') depending on the respective power stroke per unit time at the associated opening time (14) openable and closable controllable at the associated closing time (15), that the negative pressure consumer in the working cycle of the sheet-processing machine can be acted upon during each working cycle with blown air, in a memory (13) of the control unit (1) a plurality of different Blasluftbeginnzeitpunkte (16) and Blasluftendezeitpunkte (17) are stored, depending on several different numbers of working cycles per unit of time and the beginning and the end of the Blasluftbeaufschlagung per power stroke depending on the respective power stroke per unit time of the control unit (1) is switchable, wherein of the control unit (1) of the outlet of the ejector (3) for Blasluftbeginnzeitpunkt (16) closable and openable to Blasluftendezeitpunkt (17).

Description

The invention relates to a device for supplying a vacuum consumer of a sheet-processing machine in a working cycle of the sheet-processing machine with negative pressure, openable by a control unit between a source of air pressure and an ejector first valve openable and closable controllable and an inlet during each working cycle Cross section of the ejector with an overpressure air flow of the air pressure source can be acted upon, which flows through the ejector to an outlet leading to the atmosphere, wherein between the inlet and the outlet of the ejector, a radial port opens into the ejector, which leads via a suction line to the vacuum consumer ,

In such facilities ( EP 1 020 388 B1 ) A negative pressure is generated at the radial port of the ejector as it flows through air, which leads to a negative pressure of the vacuum consumer such as a nipple. By opening and closing the first valve, the negative pressure is applied to the vacuum consumer in the working cycle of the sheet-processing machine. Between the ejector and the vacuum consumer, a controllable quick exhaust valve is arranged, through which a connection from the air pressure source to the vacuum consumer can be opened. Thus, a quick reduction in vacuum and thus a quick release of the sheet can be done by the vacuum consumers.

The object of the invention is to provide a device of the type mentioned, which is simple in construction and allows a quick reaction of the vacuum consumers to at least largely optimal times during a variably selectable working cycle.

This object is achieved in that the sheet processing machine with several different work cycles per unit time is operable and stored in a memory of a control unit according to several different opening times and associated closing times of the first valve depending on several different numbers of work cycles per unit time and from the control unit, the first valve depending on the respective power stroke per unit time at the associated opening time openable and closable controllable at the associated closing time is that the vacuum consumers in the power stroke of the sheet processing machine can be acted upon during each work cycle with blowing air, wherein in a memory of the control unit several different Blasluftbeginnzeitpunkte and Blasluftendezeitpunkte are stored, which differ depending on several different are different numbers of work cycles per unit time and the beginning and the end of Blasluftbeaufschlagung per work cycle depending on the respective power stroke per unit time of the control unit is switchable, which is closed by the control unit, the outlet of the ejector for Blasluftbeginnzeitpunkt and openable Blasluftendezeitpunkt.

As a result of this design, the at least largely optimized activation of the first valve is automatically effected according to the selected working cycle of the sheet-processing machine, so that the vacuum consumer is supplied with negative pressure at the right time and for the correct period of time.

Since the operator does not have to make adjustments to the sheet processing machine, no interruption of production is required, resulting in higher output of sheets.

In order to end the negative pressure of the vacuum consumer by its Blasluftbeaufschlagung exactly and automatically adjust the at least approximately optimal time of Blasluftbeaufschlagung is the vacuum consumers in the working cycle of the sheet-processing machine during each working cycle acted upon with blown air.

Again, no interruption of production is required because the operator does not have to make any adjustments to the sheet-processing machine.

If an arc is detected by the negative pressure consumer acted upon by negative pressure, an immediate release of a sheet from the vacuum consumer is ensured by the blowing air.

Such a Blasluftbeaufschlagung the vacuum consumer can also be used as a cleaning pulse for cleaning the vacuum consumer.

The device according to the invention has a free paramentability of the timing of the first and / or second valve, wherein the timing of the process and the speed can be adjusted individually. It has a very high smoothness and has a low energy consumption, since only energy consumption occurs when suction or blown air is needed. The noise level is greatly reduced and it is no polluting and possibly dissipated heat generated. The structure with only a few components is inexpensive and Space saving. Nevertheless, very high work cycles can be driven.

Characterized in that from the control unit, the outlet of the ejector for Blasluftbeginnzeitpunkt closable and openable for Blasluftendezeitpunkt is actuated, the Blasluftbeaufschlagung after a negative pressure is applied solely by closing the outlet of the ejector. As a result, the air flow supplied to the inlet of the ejector is not fed via the outlet of the atmosphere but at the closed outlet as a blast air flow to the radial end of the ejector.

For this purpose, a second valve can be connected downstream of the outlet of the ejector in a simple manner, the passage to the Blasluftbeginnzeitpunkt is closable and openable for Blasluftendezeitpunkt controllable.

In this case, preferably, the closing time of the first valve approximately correspond to the Blasluftendezeitpunkt.

For fast switching of the valves, the first valve and / or the second valve are preferably solenoid valves.

The opening times and the closing times and / or the Blasluftbeginnzeitpunkte and the Blasluftende time points are preferably determined or calculated empirically for the different work cycles per unit time and then stored in the memory of the control unit.

A definition possibility is that the opening times and the closing times and / or the Blasluftbeginnzeitpunkte and the Blasluftendezeitpunkte are stored as rotational angular positions of a rotatably driven with one revolution per power stroke component of the sheet processing machine.

In this case, the rotatably driven component may be a single-turn shaft of the sheet-processing machine.

The respective rotational movement and / or rotational speed of the rotatably driven component of the sheet-processing machine can be detected by a rotary encoder and fed to the detected values of the control unit.

Another definition is that the opening times and the closing times and / or the Blasluftbeginnzeitpunkte and the Blasluftendezeitpunkte are stored as linear path positions of a movable with a reciprocating stroke per power stroke component of the sheet processing machine.

In this case, the component driven with a return stroke per working cycle can be a presser foot of the sheet-processing machine.

The linear positions can be detected by a position sensor and the detected values can be fed to the control unit.

Preferably, the position sensor is an analog sensor.

Preferred negative pressure consumers may be a vacuum cleaner or a suction strip or a turning drum or a stacker having a plurality of sucker arranged side by side.

One or more ejectors can be acted upon by an air pressure source with an air flow having overpressure.

Also, each vacuum consumer or each group of several vacuum consumers of a plurality of vacuum consumers having Unterdruckverbraucherleiste be associated with an ejector.

It is likewise possible for each individual ejector and / or each group of ejectors formed from a plurality of ejectors to be preceded by a first valve which can be actuated separately and opened.

If in this case the openable controllable first valves are manually active and inactive switchable, so that only the ejectors of an ejector bar can be switched to produce negative pressure corresponding to the format width of a sheet to be processed. By inactive switched ejectors a short circuit to the atmosphere is avoided.

A particularly short path from the generation of suction air to the vacuum consumer is achieved when an ejector or an ejector row forms a structural unit with a vacuum consumer or a vacuum consumer series.

If the overpressure and / or the amount of air supplied to the ejector or blowers can be variably adjusted, then the negative pressure at the vacuum consumer can depend on further criteria, such as e.g. the bow texture, air permeability, bow weight and bow surface are set.

• 1 eine schematische Darstellung einer Einrichtung zur Versorgung eines Unterdruckverbrauchers einer Bogen verarbeitenden Maschine
• 2 eine schematische Darstellung von einem ersten Ventil und einem Ejektor mit nachgeschaltetem geöffneten zweiten Ventil einer damit ergänzten Einrichtung nach 1
• 3 eine erstes Ausführungsbeispiel einer schematischen Darstellung von einem ersten Ventil und einem Ejektor mit nachgeschaltetem geschlossenen zweiten Ventil einer damit ergänzten Einrichtung nach 1
• 4 eine schematische Darstellung eines weiteren Ausführungsbeispiels von ersten Ventilen und Ejektoren mit nachgeschaltetem zweiten Ventil

An embodiment of the invention is illustrated in the drawing and will be described in more detail below. Show it

• 1 a schematic representation of a device for supplying a vacuum consumer of a sheet-processing machine
• 2 a schematic representation of a first valve and an ejector with downstream open second valve of a device supplemented with it 1
• 3 a first embodiment of a schematic representation of a first valve and an ejector with downstream closed second valve of a supplemented device according to 1
• 4 a schematic representation of another embodiment of the first valves and ejectors with downstream second valve

In the 1 schematically illustrated device for supplying a vacuum consumer of a sheet-processing machine has a control unit 1 on, by the closed in normal position first valves 2 . 2 ' . 2 '' and 2 ''' are openable controllable. The first valves 2 . 2 ' . 2 '' and 2 ''' are designed as solenoid valves.

At the entrance of the valves 2 . 2 ' . 2 '' and 2 ''' is the pressure of an air pressure source, not shown.

By opening the passage of the valves 2 . 2 ' . 2 '' and 2 ''' is the positive pressure airflow of the air pressure source inlets 4 small cross section of ejectors 3 . 3 ' and 3 '' fed. The airflow flows straight through the ejector 3 , 3 ' 3 '' to an outlet 5 of the ejector 3 . 3 ' . 3 '' that is connected to the atmosphere.

The ejectors 3 . 3 ' . 3 '' point between inlet 4 and outlet 5 a radial connection 6 on, which in turn is connected to a vacuum consumer of the sheet processing machine.

When flowing through the ejectors 3 . 3 ' . 3 '' with a pressurized air stream is at the outlet 5 generates a negative pressure, which acts on the vacuum consumer.

The first valves 2 and 2 ' is a squeegee 7 with suckers 8th assigned as vacuum consumers, in which a plurality of ejectors 3 are integrated, in turn, each one of the suckers 8th assigned. Because the ejectors 3 directly at the suckers 8th are located, a direct largely lag-free negative pressure of the sucker 8th reached. From each of the valves 2 and 2 ' becomes one half of the ejectors 3 supplied with negative pressure.

Should a smaller sheet size than that through the squeegee 7 maximum workable sheet format can be promoted, one of the valves 2 . 2 ' stay closed and only one half of the squeegee 7 be activated.

Through the valve 2 '' is via a distributor 9 an ejector 3 ' acted upon by an air pressure having overpressure, at its radial connection 6 directly to a vacuum consumer forming individual vacuum cleaner 10 connected.

About the valve 2 ''' becomes an ejector 3 '' subjected to an overpressure airflow. The radial connection 6 of the ejector 3 ' is directly with a vacuum consumer forming, three suckers having multiple vacuum cleaner 11 connected so that from a single ejector 3 ' several suckers are subjected to negative pressure.

The sheet processing machine operates in working cycles, so that the negative pressure of the vacuum consumers must be done in these work cycles.

Therefore, the valves 2 - 2 ''' in these work cycles from the control unit 1 opened and closed controlled.

The sheet processing machine is operable with nine different working cycles per hour.

A rotary encoder 12 detects at a not shown with one revolution per power stroke rotatably driven component of the sheet-processing machine, the rotational movement of this component and passes the detected values of the control unit 1 to.

In a store 13 the control unit 1 For the nine possible work cycles per hour, with which the sheet-processing machine can be operated, opening times corresponding to each working cycle speed are appropriate 14 and closing times 15 stored. According to the encoder 12 recorded value of the current work cycles per hour are from the control unit 1 the corresponding opening time 14 and closing time 15 selected within a work cycle and the valves 2 - 2 ''' controlled accordingly.

In the present case, the encoder has 12 10 000 Working cycles detected per hour, so that the control unit 1 the valves 2 - 2 ''' opens at 130 ° a 360 ° rotation of the rotatably driven component of the sheet-processing machine per power stroke and closing at 150 °.

In the store 13 are still Blasluftbeginnzeitpunkte 16 and blowing air end times 17 filed at the nine working cycles per hour. During these times will be over the radial ports 6 the ejectors 3 - 3 '' supplied to the vacuum consumers blowing air.

One way of blowing air is in the 2 to 4 shown. This is done by an outlet 5 the ejectors 3 - 3 '' downstream second valve 18 closed the connection to the atmosphere between the Blasluftbeginnzeitpunkt and the Blasluftendezeitpunkt during a power stroke. The second valve 18 is a solenoid valve.

As in 2 can be shown, with open passage of the second valve 18 the over the first valve 2 - 2 '' the ejector 3 - 3 '' supplied pressurized air through the outlet 5 flow to the atmosphere and so on the radial port 6 generate a negative pressure which is supplied to the vacuum consumer.

Is through the second valve 18 the outlet 5 closed, there is a backwater in the ejector 3 - 3 '' and to blow out through the radial port 6 , which is supplied to the vacuum consumer.

Thus, in a simple manner, the detection and transport of a sheet can be terminated immediately by a negative pressure applied to vacuum consumers by the vacuum consumers is acted upon with blowing air and repels the bow.

In 4 is shown that the inlets 4 of four ejectors 3 over two first valves 2 can be acted upon with a pressurized air flow, the four outlets 5 the ejectors 3 to a common second valve 18 can be performed so that results in a few components requiring structure.

LIST OF REFERENCE NUMBERS

1

control unit

2

first valve

2 '

first valve

2 ''

first valve

2 '' '

first valve

3

ejector

3 '

ejector

3 ''

ejector

4

Inlet

5

outlet

6

radial connection

7

squeegee

8th

sucker

9

distributor

10

Single sucker

11

Multiple sucker

12

encoders

13

Storage

14

Opening times

15

Closing times

16

Blasluftbeginnzeitpunkte

17

Blasluftendezeitpunkte

18

second valve

Claims (14)

Device for supplying a vacuum consumer of a sheet-processing machine in a working cycle of the sheet-processing machine with negative pressure, wherein by a control unit between a air pressure source and an ejector (3, 3 ', 3'') arranged first valve (2, 2', 2 '') openable and closable controllable during each work cycle and an inlet of small cross-section of the ejector (3, 3 ', 3'') can be acted upon with an overpressure air flow of the air pressure source, by the ejector (3, 3', 3 '' ) to an atmosphere leading to the outlet (5), wherein between the inlet (4) and the outlet (5) of the ejector (3, 3 ', 3'') a radial port (6) in the ejector (3, 3 ', 3'') leads, which leads via a suction line to the vacuum consumer, characterized in that the sheet-processing machine with a plurality of different working cycles per unit time is operable and in a memory (13) of a control unit (1) e ntsprechend several different opening times (14) and respectively associated closing times (15) of the first valve (2, 2 ', 2'',2''') depending on a plurality of different numbers of work cycles per unit time are stored and by the control unit (1 ) the first valve (2, 2 ', 2'',2''') depending on the respective power stroke per unit time at the associated opening time (14) openable and closable controllable at the associated closing time (15), that the vacuum consumers in Operating cycle of the sheet-processing machine during each working cycle can be acted upon with blown air, wherein in a memory (13) of the control unit (1) a plurality of different Blasluftbeginnzeitpunkte (16) and Blasluftendezeitpunkte (17) are stored, depending on a plurality of different numbers of work cycles per unit time are and the beginning and the end of Blasluftbeaufschlagung per stroke Depending on the respective power stroke per unit time of the control unit (1) is switchable, wherein from the control unit (1) of the outlet of the ejector (3) for Blasluftbeginnzeitpunkt (16) closable and the Blasluftendezeitpunkt (17) can be opened openable. Setup after Claim 1 , characterized in that the outlet (5) of the ejector (3), a second valve (18) is connected downstream, the passage to the Blasluftbeginnzeitpunkt (16) closable and the Blasluftendezeitpunkt (17) can be opened openable. Device according to the preceding claims, characterized in that the closing time (15) of the first valve (2) corresponds approximately to the blown air end time (17). Device according to one of the preceding claims, characterized in that the opening times (14) and the closing times (15) and / or the Blasluftbeginnzeitpunkte (16) and the Blasluftendezeitpunkte (17) as rotational angular positions of a rotatably rotatably per working cycle driven component of the arc processing machine are stored. Setup after Claim 4 , characterized in that the rotatably driven member is a Eintourenwelle the sheet-processing machine. Furnishing according to one of the Claims 4 and 5 , characterized in that the rotational movement and / or the rotational speed of the rotatably driven component of the sheet-processing machine by a rotary encoder (12) detectable and the detected values of the control unit (1) can be fed. Furnishing according to one of the Claims 1 to 4 , characterized in that the opening times and the closing times and / or the Blasluftbeginnzeitpunkte and the Blasluftendezeitpunkte are stored as Linearwegpositionen one with a reciprocating stroke per power stroke movably driven component of the sheet processing machine. Setup after Claim 7 , characterized in that the driven with a reciprocating stroke per power stroke component is a presser foot of the sheet-processing machine. Device according to one of the preceding claims, characterized in that the vacuum consumer is a suction device (8) or a suction strip (7) having a plurality of juxtaposed suction devices or a turning drum or a destacker. Device according to one of the preceding claims, characterized in that one or more ejectors (3) can be acted upon by an air pressure source with an air flow having overpressure. Device according to one of the preceding claims, characterized in that an ejector (3 '') is associated with each vacuum consumer or each group of several vacuum consumers of a vacuum consumer bar having a plurality of vacuum consumers. Device according to one of the preceding claims, characterized in that a separate openable controllable first valve (2) is connected upstream of each individual ejector (3) and / or each of a plurality of ejectors (3) formed group of ejectors (3). Setup after Claim 10 , characterized in that the openable controllable first valves (2) are manually active and inactive switchable. Device according to one of the preceding claims, characterized in that the overpressure and / or the air quantity of the or the ejectors supplied air flow is variably adjustable.

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