EP0775655B1 - Vacuum- and/or compressed air controller - Google Patents

Abstract

The air blast controller has an electrically controllable valve whose outlet is directly connected to the pressure connection (32) of the load device via which the pressure or vacuum is delivered through a feed line. The valve is driven by an electronic control device (12) and is connected to the feed line (4). The outlet of the electrically controllable valve can be connected to the pressure connections of several loads. The load and valve can form a single unit or can have a common housing (18). The load device can be a suction device of a sheet feeder.

Description

The invention relates to a suction air control for consumers Feeder for feeding sheets to a sheet processing Machine, in particular a printing press, with a pressure connection of the consumer via a supply line from the negative pressure Vacuum source can be acted upon, at the pressure connection of the Consumer immediately an outlet of an electrically controllable valve is connected, which can be controlled by a control device, and the consumer one with one of the negative pressure of the negative pressure source Actuated suction surface is provided, and on a blast air control for consumers of a feed device for feeding Sheet to a sheet processing machine, especially one Printing machine, wherein a pressure connection of the consumer via a Supply line can be acted upon by the excess pressure of an excess pressure source, an outlet of an electrical at the pressure connection of the consumer controllable valve is connected by a control device is controllable, and the consumer is one of the excess pressure the pressurizable blower nozzle and the electrically controllable Valve depending on parameters that can be entered from the electronic Control device is controllable.

Controls of this type are used in particular in the case of sheet feeders for sheets processing machines for supplying vacuum with vacuum or required from blow nozzles with overpressure. From the respective sub or pressure source and the corresponding pneumatic control unit lead relatively long supply lines to the consumers. The most varied Sheets such as paper, cardboard, cardboard, corrugated cardboard or Sheet metal that should be processable require an adjustment of the intensity as well as the time of the respective pressurization or vacuum application on the consumer.

This is only possible with restrictions in the known controls.

From EP-A-0 194 511 is a suction air control after the beginning known type known. It is by means of an adjustable frequency generator the opening and closing frequency of the valve can be changed.

From DE-C-615 746 it is known to use an electromagnet Lift anchor against the force of a spring, being on the anchor a piston guided in a cylinder is arranged. Through the lifting movement of the piston is connected to the cylinder chamber Suction nozzle creates a negative pressure for detecting an arc.

From US-A-4 513 957, which is also cited, is a sheet dispenser known, in the case of a sheet stack by means of vacuum Suction cups the top sheet can be removed and dispensed is. To ensure that the sheets are securely gripped, there are two groups of suction cups. It is found that from the The first group of suction cups does not transport the sheet A control of the second group via a microprocessor control of suction cups, which then ensures that the top sheet is gripped securely and transported to an output.

In a blown air control it is known from EP-A-0 503 623 electrical valve depending on parameters that can be entered from an electrical one Control unit.

The object of the invention is therefore controls of the aforementioned Way of creating by which the amount of pressure and / or the temporal The pressure or vacuum supply of the consumers can be precisely regulated.

This object is achieved in that at a Suction control the electrically controllable valve from an electronic Control unit depending on those that can be entered into the control device Parameters of the angle of rotation and the clock of the sheet processing Machine can be controlled and that with a blown air control Enterable parameters of the angle of rotation and the cycle of the sheet processing Machine and the pressure connection of the blow nozzle are immediate is connected to the outlet of the electrically controllable valve.

This design ensures that the negative pressure generated by the negative pressure source or the excess pressure generated by the pressure source in a sufficient Volume immediately and in the desired and constant Height at the consumer so that there is no time delay due to empty pumps or filling the in particular different line lengths the supply system having different consumers occur can. Significant fluctuations in the pressure or vacuum level can occur and the proper treatment of the funded Tang negative arc.

This is particularly important when the sheet processing machine clocked works and the sheets fed to her exactly in her work cycle Need to become.

Changes in the timing of consumer work and in the amount of their pressurization can be according to the control through the electronic control device directly at the consumer be effective. This is e.g. also fine adjustment of the pressure or negative pressure in the pressure level and in the chronological sequence exactly possible.

This ensures an accurate and optimally processing machine for the sheet set mode of operation of feeding the sheets to be processed to the sheet processing machine.

Are the pressure connections to the outlet of the electrically controllable valve several consumers connected so that several can be together arranged similar consumers with a single Valve pressure and vacuum pressures are applied exactly evenly. This means that this consumer group is becoming unevenly effective excluded, so that the exact sheet conveyance is ensured becomes.

It is particularly space-saving when consumers and electrical controllable valve form a structural unit. They also have consumers and electrically controllable valve a common housing, so the number of components required is also reduced.

Particularly precise switching movements and exact switching positions in particular Intermediate positions are possible. If the electrically controllable Valve is a solenoid valve.

The parameters of the suction or blast air control can be controlled by sensors in particular on the sheet processing machine and the electronic control device can be fed.

It is also possible for the parameters to be changed manually electronic control device can be entered. In order to can e.g. Data on the type and quality of each fed sheet to the control device become. According to the supplied data, and / or regulation depending on the characteristic e.g. the chronological sequence, the beginning and the end as well as the pressure level and the pressure curve of the pressure or Negative pressurization of the consumer by the electronic control device.

Depending on the size to be controlled, this can be done electrically controllable valve a way and / or a pressure control and / or a flow control valve. Become several of these functions can be done the different Valve functions through an integrated structure Valve.

If the electrically controllable valve is a 2/2-way valve, in its first switch position the feed line connected to the pressure connection of the consumer and in its second switch position supply line and pressure connection of the consumer blocked the beginning and end of a vacuum or pressurization of the consumer can be controlled precisely. The consumer is preferred a sucker of a sheet feeder.

Particularly beneficial when training the consumer as a sucker for lifting the top sheet one It is stack of sheets when the electrically controllable Valve is a 3/2-way valve, in its first switching position the supply line with the pressure connection of the Connected consumer and in its second switching position the supply line shut off and the pressure connection of the consumer with a vent connected is. It is in the first switch position the vacuum cleaner is pressurized by the vacuum source and not only in the second switch position shut off from the vacuum source but also ventilated at the same time so that the grasped by the vacuum cleaner and raised sheets are easily transported and the Suction cup can move to its original position.

These functions of the vacuum cleaner are even more precise and faster when the electrically controllable valve is on 3/2-way valve is in the first switch position Supply line with the pressure connection of the consumer connected and in its second switching position the feed line shut off and the pressure connection of the consumer connected to an overpressure source or is connectable.

In doing so, the ventilation of the vacuum cleaner should be in its time and possibly also in their chronological sequence and in their Intensity can be determined in the second Switch position of the pressure connection of the consumer a control valve can be connected to a positive pressure source his. For this purpose, the control valve is preferably an electric one controllable control valve, which is also by the electronic control device can be controlled can.

The control valve can be a 2/2-way valve, its passage blocked in the first switch position is and in the second switching position the source of excess pressure connects to the electrically controllable valve.

Figur 1

eine Seitenansicht einer Saug- und Blasluftsteuerung

Figur 2

einen Querschnitt einer Sauger/Ventileinheit in Normalstellung

Figur 3

einen Querschnitt der Sauger/Ventileinheit nach Figur 2 in der Saugstellung

Figur 4

ein Schaltbild der Sauger/Ventileinheit nach Figur 2

Figur 5

ein Schaltbild eines zweiten Ausführungsbeispiels einer Sauger/Ventileinheit

Figur 6

ein Schaltbild eines dritten Ausführungsbeispiels einer Sauger/Ventileinheit

Figur 7

ein Schaltbild eines vierten Ausführungsbeispiels einer Sauger/Ventileinheit.

Embodiments of the invention are shown in the drawing and are described in more detail below. Show it

Figure 1

a side view of a suction and blowing air control

Figure 2

a cross section of a suction / valve unit in the normal position

Figure 3

a cross section of the suction / valve unit according to Figure 2 in the suction position

Figure 4

a circuit diagram of the suction / valve unit according to Figure 2

Figure 5

a circuit diagram of a second embodiment of a suction / valve unit

Figure 6

a circuit diagram of a third embodiment of a suction / valve unit

Figure 7

a circuit diagram of a fourth embodiment of a suction / valve unit.

The suction and blowing air control shown in Figure 1 for a sheet feeder has one over a sheet stack 1 arranged suction head 2, on which a vacuum cleaner 3 is arranged. From the vacuum cleaner 3 leads from a feed line, not shown, a supply line 4. The separating suction cup 3 is each uppermost sheet of the sheet stack 1 can be detected and raised, to then from a further conveyor, not shown such as. also arranged on the suction head 2 Drag vacuums to be captured and transported.

In the conveying direction 5 behind the sheet stack 1 is in The height of the uppermost arch is approximately horizontal towards it a blowing air nozzle 6 is arranged through which Blown air is blown against the uppermost sheet on the face is so that they are separated from each other, or that under that at its lower end through the separating suction 3 raised top arc formed an air cushion that is a separation of the top arc its entire length is caused by the arch below.

Via a feed line 7, the blowing nozzle 6 is one Not shown pressure source with under pressure stagnant air.

Between the separating suction device 3 and its feed line 4 and between the blowing nozzle 6 and its feed line 7 a solenoid valve 8 and 9 is arranged, respectively that the negative pressure or overpressurization of Separating suction device 3 or blowing nozzle 6 is controllable. To control is the solenoid valve 8 via a control line 10 and the solenoid valve 9 via a control line 11 with an electronic control device 12 connected. If there are drag vacuums, they can in the same way by the electronic control device be controllable.

The data lines 13 and 14 are electronic Control device 12 data of a not shown Printing machine feedable to which the sheets of the sheet stack 1 are funded individually.

The data from the printing press can be recorded by sensors e.g. Information about speeds, the angle of rotation or the work cycle of the printing press. About that the pressure values detected by sensors can also be used in the feed lines 4 and 7 of the electronic Control device 12 are supplied.

Additional data such as e.g. about the type and quality of the sheets to be conveyed manually entered the electronic control device 12 become. According to the data supplied control of the solenoid valves depending on the program 8 and 9 by the electronic control device 12th

In Figures 2 and 3, the solenoid valve 8 and Vacuum cleaner 3 in cross section both in the raised Normal position as well as in the lowered suction position shown. Solenoid valve 8 and vacuum cleaner 3 are closed summarized one unit and have a common Housing 18. In the housing 18 is a cylinder bore 19 formed in which a stepped piston 20th arranged with its large step 21 axially movable is. The step piston protrudes with its small step 22 20 down through a bore 23 of the same cross section out of the housing 18 and carries it out of the housing 18 projecting end a suction nozzle 24.

The stepped piston 20 is coaxial with a bore 25 provided on a suction surface 26 of the suction nozzle 24th leads to the outside. In the lower end area of the stepped piston 20 branch suction bores 27 from the bore 25 and also open into the suction surface 26.

The step piston 20 is through a small step 22 enclosing cylindrical compression spring 28 according to his biased towards the upper end position. The is supported Compression spring 28 with its upper end on the large step 21 of the stepped piston 20 and with its lower end on Transition from cylinder bore 19 to bore 23.

The lowest possible position of the stepped piston 20 is compressed by the compression spring 28 on block defined (Figure 3).

The top position of the stepped piston (Figure 2) is by the abutment of the stepped piston 20 against a stop defined, which is formed by a stop plate 29 is. The stop disc 29 is coaxial in one at the cylinder bore 19 adjoining guide bore 30 larger diameter than the cylinder bore 19 slidably arranged by a certain amount and has axial spacers 31 against which the Step piston 20 comes to the plant. Through the spacers 31 ensures that the bore 25 always communicates with the face of the large step 21.

A pressure port 32 of the suction pad 3 is two Bores 33 and 34 connected to the cylinder bore 19. The bore 33 opens into the bore 23 facing End area in the cylinder bore 19, while the bore 34 in the opposite end of the Cylinder bore 19 opens. This is in the raised Normal position of the stepped piston 20 between the small step 22 and the cylinder bore wall Annulus 35 with both holes 33 and 34 with connected to the pressure connection 32 and pressurizable.

In the lowered suction position, the annular space 35 is only still connected to the pressure connection 32 via the bore 33. The bore 34 then connects the pressure connection with the cylinder bore 19 above the large step 21. This area of the cylinder bore 19 is then over the bore 25 connected to the suction surface 26, so that this negative pressure is supplied to detect an arc becomes.

Between the pressure port 32 of the vacuum cleaner and a feed line connector 36 to which the feed line 4 can be connected, is designed as a magnetic valve 3/2-way valve 37 arranged.

The 3/2-way valve has one in a valve housing 38 between two end positions axially movable armature 39, which is enclosed by a coil 40 fixed to the housing is. The path of movement of the armature 39 is vertical aligned. In the interior 41 of the valve housing 38 A connection 42 opens from below to the feed line connection 36 and from above a connection 43 to the outside air. The mouths of connections 42 and 43 are as opposing valve seats 44 and 45 are formed. The ends of the armature 39 facing them in each case have insert parts 46 made of a sealing material and form valve members which are connected to the valve seats 44 and 45 work together.

Supported by a support of the coil 40 fixed to the housing Compression spring 47 is the armature 39 against the lower one Valve seat 44 biased so that when not energized Coil 40 always closed the valve seat 44 is.

The armature 39 is countered by energizing the coil 40 the force of the compression spring 47 raised and with the Insert part 46 of its upper end against the valve seat 45 pressed so that the connection 43 of the interior 41st shut off from the outside air and the interior 43 with the Lead connection 36 connected via the connection 42 becomes. Since the interior 41 continues to permanently with the Pressure port 32 is connected, it depends on the control of the coil 40 either with the feed line connection 36 or connected to the outside air.

When the coil 40 is not activated and outside air is applied the pressure port 32 is the large stage 21 of the stepped piston 20 on both sides of the outside air acted on, so that the stepped piston 20 through the Compression spring 28 is moved to its upper position (Figure 2).

If the coil 40 is energized, the Valve seat 44 and closing of the valve seat 45. Since permanent negative pressure at the supply line connection 36 is applied, largely without delay via the pressure port 32 and the holes 33 and 34 a Pressurization of the annular space 35. Since the Annulus 35 facing away from the large stage 21 the bore 25 is connected to the outside air the stepped piston 20 against the force of the compression spring 28 and moves to its suction position (Figure 3).

With this downward movement, the large stage 21 starts the mouth of the bore 34 over, so that then with the side of the stepped piston facing away from the annular space 35 20 is connected.

The suction surface 26 arrives approximately in the suction position Suction nozzle 24 on the top sheet of the sheet stack 1 to edition. This closes the hole 25 and the suction holes 27 through the top arc, so that through the bore 34 also on the suction surface 26 facing away from the large step 21 of the step piston 20 pressurized and the stepped piston 21 is lifted with the detected sheet. By switching the 3/2-way valve 37 is subjected to outside air of the vacuum cleaner 2 and thus an acceleration the lifting movement and reduction of the holding force of the bow so that it is raised from the Position easily by e.g. a vacuum cleaner from Separating suction cups 3 are pulled off in the conveying direction 5 can.

A circuit diagram of the 3/2-way valve 37 is shown in FIG. 4 shown, the individual parts with the same Reference numerals are provided. To the supply line connection 36, a vacuum source 49 is connected.

The embodiment shown in Figure 5 as a circuit diagram largely corresponds to the embodiment from Figures 2 to 4. The only difference is in that the connection 43 is not to the outside air but leads to an overpressure source 48, so that the Ventilation of the vacuum cleaner can be done faster.

The embodiment of Figure 6 is another Modification of the training example in FIG. 5 the pressure source 48 is not immediate but via a 2/2-way valve designed as a solenoid valve 50 with the connection 43 of the 3/2-way valve 37 connected. The 2/2-way valve is by an electromagnet 51 50 from its position shown blocked passage against the force of a spring 52 adjustable in its position with open passage. This enables controlled ventilation of the vacuum cleaner 3 via the 3/2-way valve 37.

Figure 7 shows a simple embodiment of a Suction air control according to the invention for a vacuum cleaner 3 with a 2/2-way valve 53, which by a Electromagnet 54 against the force of a spring 55 between a supply line connection 36 of the valve connecting to a pressure port 32 of the vacuum cleaner Position and a locking position switchable is.

reference numeral

1

Sheet stack

2nd

Suction head

3rd

Separating suction

4th

Supply line

5

Direction of conveyance

6

Blow nozzle

7

Supply line

8th

Solenoid valve vacuum cleaner

9

Blow nozzle solenoid valve

10th

Control line separating suction

11

Control line blowing nozzle

12th

electrical control device

13

Data line

14

Data line

18th

casing

19th

Cylinder bore

20th

Stepped piston

21

great stage

22

small level

23

drilling

24th

Suction nozzle

25th

drilling

26

Suction surface

27

Suction hole

28

Compression spring

29

Stop disc

30th

Pilot hole

31

Spacers

32

Pressure connection

33

drilling

34

drilling

35

Annulus

36

Feed line connection

37

3/2-way valve

38

Valve body

39

anchor

40

Kitchen sink

41

inner space

42

connection

43

connection

44

Valve seat

45

Valve seat

46

Insert part

47

Compression spring

48

Overpressure source

49

Vacuum source

50

2/2 way valve

51

E-magnet

52

feather

53

2/2 way valve

54

E-magnet

55

feather

Claims (15)

1. Suction control for user devices of a feed unit for feeding sheets to a sheet treating machine, particularly a printing press, wherein a pressure connection (32) of the user device can be subjected via a feed lead to reduced pressure from a source of reduced pressure (49), wherein connected directly to the pressure connection (32) of the user device is an outlet of an electrically controllable valve, which can be controlled by a control unit (12), and wherein the user device is a sucker provided with a suction surface (26) which can be subjected to reduced pressure from the source of reduced pressure (49), characterised in that the electrically controllable valve is controllable by an electronic control unit (12) dependent upon the parameters of the rotational angle and the timing of the sheet treating machine which can be input into the control unit (12).
2. Blown air control for user devices of a feed unit for feeding sheets to a sheet treating machine, particularly a printing press, wherein a pressure connection (32) of the user device can be subjected via a feed lead (4) to increased pressure from a source of excess pressure (48), wherein connected to the pressure connection (32) of the user device is an outlet of an electrically controllable valve, which can be controlled by a control unit (2) and wherein the user device is a blowing nozzle (6) which can be subjected to excess pressure from the source of excess pressure (48) and the electrically controllable valve is controllable in dependence on parameters input by the electronic control unit (12), characterised in that the input parameters are the rotational angle and the timing of the sheet treating machine and the pressure connection (32) of the blowing nozzles (6) is connected directly to the outlet of the electrically controllable valve.
3. Control according to one of the preceding Claims, characterised in that connected to the outlet of the electrically controllable valve are the pressure connections of several user devices.
4. Control according to one of the preceding Claims, characterised in that the user device and electrically controllable valve constitute one constructional unit.
5. Control according to Claim 4, characterised in that user device and electrically controllable valve have a common housing (18).
6. Control according to one of the preceding Claims, characterised in that the electrically controllable valve is a magnetic valve.
7. Control according to one of the preceding Claims, characterised in that the parameters can be captured by sensors and can be fed to the electronic control unit (12).
8. Control according to one of Claims 1 to 6, characterised in that the parameters can be input manually to the electronic control unit (12).
9. Control according to one of the preceding Claims, characterised in that the electrically controllable valve is a distribution and/or a pressure control and/or a volume control valve.
10. Control according to Claim 9, characterised in that the electrically controllable valve is a 2/2 distribution valve (53) in the first switching position of which the feed lead (4) is connected with the pressure connection (32) of the user device and in its second switching position feed lead (4) and pressure connection (32) of the user device are blocked.
11. Control according to Claim 9, characterised in that the electrically controllable valve is a 3/2 distribution valve (37) in the first switching position of which the feed lead (4) is connected with the pressure connection (32) of the user device and in its second switching position the feed lead (4) is blocked and the pressure connection (32) of the user device is connected with a venting opening (43).
12. Control according to Claim 9, characterised in that the electrically controllable valve is a 3/2 distribution valve in the first switching position of which the feed lead (4) is connected with the pressure connection (32) of the user device and in the second switching position of which the feed lead (4) is blocked and pressure connection (32) of the user device is connected or connectable to a source of excess pressure (48).
13. Control according to Claim 12, characterised in that in the second switching position, the pressure connection (32) of the user device is connectable via a control valve with a source of excess pressure (48).
14. Control according to Claim 13, characterised in that the control valve is an electrically controllable control valve.
15. Control according to Claim 13, characterised in that the control valve is a 2/2 distribution valve (50), the passage in which is blocked in the first switching position and which, in the second switching position connects the source of excess pressure (48) with the electrically controllable valve.

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