Printing press

Abstract

A printing press (10) has at least one electric motor (14), which is arranged at a distance of less than 0.5 m from an emission source (18). At least one explosion protection wall (22) is provided, such that the thread measure (F) between the emission source (18) and the electric motor (14) is greater than 0.5 m.

Claims

1. A printing press comprising: at least one electric motor, the at least one electric motor being arranged at a distance of less than 0.5 meters from an emission source of solvent vapors, wherein the emission source is one or more of an anilox roller, a pressure cylinder, a chambered doctor blade bar, an ink tray, or an imprinted web of material; and at least one explosion protection wall, the at least one explosion protection wall enclosing the at least one electric motor on at least two sides of the at least one electric motor and having an opening on an opposite side of the at least one electric motor from the emission source; wherein a thread measure through the opening and between the emission source and the at least one electric motor is greater than 0.5 meters, wherein the thread measure is a shortest free path connecting two points to each other while skirting obstacles.

2. The printing press of claim 1, wherein the at least one explosion protection wall is part of a labyrinth structure.

3. The printing press of claim 1, wherein the at least one explosion protection wall is part of a housing open at one end.

4. The printing press of claim 3, wherein the housing has the opening on a side of the at least one electric motor, the at least one electric motor facing away from the emission source.

5. The printing press of claim 1, wherein the emission source is the ink tray, which is designed to hold solvent-containing ink up to a maximum level, wherein the at least one electric motor is arranged relative to the ink tray such that a minimum thread measure between the maximum level and the at least one electric motor without the at least one explosion protection wall is less than 0.5 meters, and the at least one explosion protection wall is designed such that the minimum thread measure through the opening and between the maximum level and the at least one electric motor with the at least one explosion protection wall is greater than 0.5 meters.

6. The printing press of claim 1, wherein the emission source is the ink tray.

7. The printing press of claim 1, wherein the at least one electric motor does not have an explosion-protected design.

8. The printing press of claim 1, wherein the at least two sides include a top, a bottom, and a side between the top and the bottom, and the at least one explosion protection wall includes a top covering the top of the at least one electric motor, a bottom below the bottom of the at least one electric motor, and a side between the top and the bottom of the at least one explosion protection wall and adjacent the side of the at least one electric motor.

9. A printing press comprising: an electric motor; an ink tray that emits an ignitable composition, the ink tray provided at a same height as the electric motor in the printing press; and an explosion protection wall enclosing the electric motor on at least two sides of the electric motor and having an opening on an opposite side of the electric motor from the ink tray.

10. The printing press of claim 9, wherein a minimum thread measure between the ink tray and the electric motor is greater than 0.5 meters, wherein the minimum thread measure is a shortest free path through the opening and connecting the electric motor and the ink tray while avoiding obstacles.

11. The printing press of claim 9, wherein the explosion protection wall is cuboidal.

12. The printing press of claim 9, wherein the opening faces away from the ink tray.

13. The printing press of claim 9, wherein the explosion protection wall has a shape of an open shoe box.

14. The printing press of claim 9, wherein the explosion protection wall is collar-shaped in a circumferential direction of the electric motor to enclose the electric motor.

15. The printing press of claim 9, wherein the electric motor itself does not have an explosion-protected design.

16. The printing press of claim 9, wherein the electric motor is an adjustment drive unit of the printing press.

17. The printing press of claim 9, wherein the at least two sides include a top, a bottom, and a side between the top and the bottom, and the explosion protection wall includes a top covering the top of the electric motor, a bottom below the bottom of the electric motor, and a side between the top and the bottom of the explosion protection wall and adjacent the side of the electric motor.

18. A printing press comprising: an electric motor; an ink tray provided at a same height as the electric motor in the printing press; and an explosion protection wall between the ink tray and the electric motor, wherein the explosion protection wall encloses the electric motor on at least two sides of the electric motor and has an opening on an opposite side of the electric motor from the ink tray, and wherein a shortest unobstructed distance through the opening and connecting the electric motor and the ink tray is greater than 0.5 meters.

19. The printing press of claim 18, wherein the explosion protection wall further includes a top covering a top of the electric motor, a bottom below a bottom of the electric motor, and a side between the top and the bottom of the explosion protection wall and between the ink tray and the electric motor.

20. The printing press of claim 18, wherein the shortest unobstructed distance is greater than a shortest obstructed distance between the ink tray and the electric motor through the explosion protection wall.

Description

(1) Further benefits and features will emerge from the following description, as well as the enclosed drawings. These show:

(2) FIG. 1, in a schematic representation, a printing press according to the invention without an explosion protection wall, and

(3) FIG. 2, in a schematic representation, the printing press from FIG. 1 with an explosion protection wall.

DETAILED DESCRIPTION

(4) FIG. 1 shows a printing press 10 comprising an ink box 12 and an electric motor 14.

(5) In an alternative embodiment, the printing press 10 need not have an ink box 12.

(6) The printing press 10 for example is a flexographic printing press or a gravure printing machine.

(7) The ink box 12 is filled with fluid solvent-containing ink 16 up to a maximum level 18.

(8) The electric motor 14 is fastened to a beam 20 of the printing press 10.

(9) In the present embodiment, the electric motor 14 constitutes an adjustment drive unit of the printing press 10.

(10) The distance A between the ink box 12 and the electric motor 14 is 0.25 m.

(11) The thread measure F.sub.1 between the maximum level 18 and the electric motor 14 is 0.4 m.

(12) The distance between the maximum level 18 and the electric motor 14, disregarding the wall thickness of the ink box 12, is 0.25 m, similar to the distance A between the ink box 12 and the electric motor 14.

(13) In order to make sure that the thread measure between the emission source, constituted here by the maximum level 18, and the electric motor 14 is at least the required 0.5 m, an explosion protection wall 22 is provided (see FIG. 2).

(14) In an alternative embodiment, the emission source may be formed by any given location, especially one in or on the printing press 10, which has solvent-containing ink 16 which gives off solvent vapors to the surroundings during the operation of the printing press 10.

(15) The explosion protection wall 22 is part of a housing 24 which encloses the electric motor 14.

(16) The electric motor 14 here is arranged in the housing 24 and fastened along with it to the beam 20.

(17) The housing 24 is cuboidal and has an opening 26, arranged opposite to the ink box 12 and thus opposite to the maximum level 18. Hence, the housing 24 has the shape of an open shoe box.

(18) In particular, the housing 24 is entirely closed, apart from the opening 26, so that no solvent or solvent-containing air can pass through the housing 24. In other words, the housing 24 is tight.

(19) The explosion protection wall 22 here is collar shaped and runs in the circumferential direction, enclosing the electric motor 14.

(20) With the explosion protection wall 22, the minimum thread measure F.sub.2 between the maximum level 18 and the electric motor 14 is 0.6 m.

(21) In an alternative embodiment, the housing 24 and/or the explosion protection wall 22 can have basically any desired form, the geometry of the housing 24 and/or the explosion protection wall 22 ensuring that a sufficiently large thread measure F is ensured between the emission source and the electric motor 14.

(22) In addition or alternatively, the explosion protection wall 22 may be part of a labyrinth structure which ensures that the thread measure F between the emission source and the electric motor 14 is greater than 0.5 m.

(23) Of course, the printing press 10 is not confined to the exemplary embodiment shown in the figures. In particular, the distance A between the electric motor and the emission source may have any value between 0 and 0.5 m. Moreover, the minimum thread measure F.sub.2 can have any value above 0.5 m.

(24) Furthermore, the concept may be applied accordingly for protection distances other than 0.5 m.

(25) In this way, the thread measure F.sub.1 is extended by the explosion protection wall 22 to the thread measure F.sub.2, which ensures that the electric motor 14 is located outside a range where an ignitable air mixture can form during the operation of the printing press. Thus, an explosion of the solvent can be safely ruled out.

(26) This provides an economical printing press with an effective explosion protection.

(27) The invention is not confined to the embodiment shown. In particular, individual features of one embodiment may be combined at will with features of other embodiments, in particular independently of the other features of the corresponding embodiments.