EP0896878A1

EP0896878A1 - Device for use in a printing machine for axially reciprocating one or more sliding rollers

Info

Publication number: EP0896878A1
Application number: EP98202599A
Authority: EP
Inventors: Theodoris Johannes Engbertus Staijen; Pieter Brasser
Original assignee: Drent Holding BV
Current assignee: Drent Holding BV
Priority date: 1997-08-14
Filing date: 1998-08-03
Publication date: 1999-02-17
Also published as: JPH11115160A; NL1006772C2

Abstract

Device for use in a printing machine for axially reciprocating a sliding roller (4). In a drive shaft (6) of the printing machine being parallel to the sliding roller, a pivot pin (7) being square to it is mounted, on which a bush (8) is pivotally supported, which can be fixed e.g. by bolts (9) engaging the drive shaft (6), or in another way. The bush (8) rotatably mounts an oscillating member (14) being coupled to the shaft (3) of at least one sliding roller (4) by means of a coupling rod (15), so that when the axis (11) of the bush (8) encloses an angle with the axis (12) of the drive shaft (6), the sliding roller (4) performs an axially reciprocating movement when the drive shaft rotates.

Description

The invention relates to a device for use in a printing machine for axially reciprocating one or more rotatingly driven sliding rollers, said device having a drive shaft supported by the frame of the printing machine, which can be driven at a speed related to the speed of the rollers of the printing machine, a pivot pin extending square to the axis of the drive shaft being mounted in said drive shaft, a bush being be pivotally supported on said pin, means being provided for fixing the bush in a certain position in relation to the drive shaft in such a way that the axis of the bush can enclose an angle with the axis of the drive shaft, in which said bush rotatingly mounts an oscillating member which at a distance from the axis of the bush is coupled to the shaft of at least one sliding roller to be operated by it, in such a way that when the axis of the bush encloses an angle with the axis of the drive shaft, the sliding roller performs a reciprocating motion.
Such a device is known from US-1,607,931. With the help of this device, a sliding roller of the inking apparatus of the printing machine can perform an axially reciprocating motion under simultaneous rotation of the sliding roller. These motions are intended for properly distributing the ink brought on an ink roller, so that a smooth layer of ink is obtained. This prevents occurrence of ink lines in circumferential direction on the ink roller, due to which the quality of the printed matter produced on the machine would be adversely affected.
The water apparatus of the printing machine too can comprise one or more of the sliding rollers described above.
With the known device, the oscillating member is directly coupled to the shaft of the printing roller, which thus has to be pivotable in relation to the oscillating member. Further, the position of the sliding roller or the sliding rollers depends on the position of the oscillating member. When using a number of sliding rollers, their axes must therefore all be equally spaced from the axis of the drive shaft. With the known device, each sliding roller is driven through a gear wheel mounted thereon, said gear wheels engaging a centrally mounted gear wheel being situated on the drive shaft. The latter entails that during operation of the device, the gear wheels of the sliding rollers are always moved axially in relation to the gear wheel on the drive shaft. This may cause additional wear of the gear wheels.
The object of the invention is to remove the difficulties of the known device and to render the device more universally applicable.
According to the invention, to that end it is provided for, that through a coupling rod being substantially parallel to the drive shaft and the sliding roller, the oscillating member is coupled to an arm rotatingly connected to the shaft of the sliding roller, said arm extending substantially square to the axis of the sliding roller, in which the coupling rod can perform a certain pivoting movement in relation to the oscillating member and the arm, and the rotational movement of the sliding rollers can take place indepently from one another.
In order to make pivotal movement of the coupling rod possible, e.g. ball joints or flexible elements can be used for connecting a coupling rod to the oscillating member.
The connection of the coupling rod with the oscillating member and the arm will be such, that the coupling rod is always in a plane going through the axis of the sliding roller. The oscillating member is not allowed to perform a rotating movement around the axis of the bush, nor is the arm allowed to rotate in relation to the axis of the sliding roller. This would change the distance between the oscillating member and the sliding roller arm, as a result of which the correct reciprocating motion of the sliding roller would not be provided.
Like with the known device, the oscillating member can be coupled to more than one sliding roller. This can be done both from one single point of the oscillating member and from a number of points thereof. This will depend on the position where the oscillating member can be mounted and the position of the sliding rollers to be operated.
DE-A-1,225,204 describes a structure which employs an oscillating member which is supported and driven in a way totally different from the way described above. The oscillating member is coupled to the sliding rollers through links, the axis of a link being almost in alignment with the axis of the related sliding roller. Thus, the position of a sliding roller or the sliding rollers again depends on the position of the oscillating member.
Substantially the same as stated concerning US-1,607, 931 holds for CH-469 567. This can be appended by the information that adjustment of the position of the bush, on which the oscillating member is situated, takes place in an entirely different way.
In US-2,581,687, the bush, on which the oscillating member is situated, is mounted on a pivot pin, that can be fixed in a number of positions on a rotating part by means of a threaded bolt. For each position, a threaded hole must be present in the rotating part. Due to this, a continuously variable and simple adjustment is not possible. The coupling between the oscillating member and the sliding roller again takes place by a member being in alignment with the axis of the sliding roller or by a rotationally supported lever.
The invention is further explained by way of an embodiment, illustrated in the drawing, in which:
Fig. 1 shows a cross-section of a portion of a printing machine in which the device according to the invention has been applied; and
Fig. 2 shows a side view of the device according to Fig. 1 in the direction of the arrow II in Fig. 1.
Fig. 1 shows in particular the frame portions 1 and 2 of the printing machine according to the invention, in which the one end of the shaft 3 of a sliding roller 4 is supported in the frame portion 1. The sliding roller 4 is rotated by means not further indicated during operation of the printing machine and is axially reciprocable in a way to be described later.
By means of bearings 5, the frame portions 1 and 2 support a drive shaft 6 that can be rotated in a way not further indicated with a speed related to the machine. The shaft 6 is provided with a pivot pin 7 on which a bush 8 is pivotable. At a distance from the pivot pin 7, the bush 8 is provided with two bolts 9 which are screwed into the bush 8 and which can be fixed by means of a nut 10. With the help of the bolts 9, the axis 11 of the bush 8 can be adjusted in relation of the axis 12 of the drive shaft 6.
The bush 8 mounts the inner ring of a bearing 13, on the outer ring of which an oscillating member 14 is situated. At a distance from the bush 8, through a coupling rod 15 the oscillating member 14 is connected to an arm 16 which is rotatingly mounted to the shaft 3 of the sliding roller 4 by means of a bearing 17. The coupling rod 15 is connected to the oscillating member 14 and the arm 16 by means of pivots or flexible connecting elements 18.
The presence of the coupling 15 is intended to prevent the oscillating member 14 from rotating with the bush 8. The coupling rod 15 and the pivots 18 together should be able to transmit both pressure forces and tensile forces so that the distance between the arm 16 and the oscillating member 14 with the oscillating motion of the member 14 remains the same.
When the bush 8 is rotated during operation of the printing machine, the oscillating member 14 will perform an oscillating movement as indicated by the arrow P in Fig. 1 and by the dot lines indicating the outer plane of the oscillating member with its extreme positions with a certain angle between the axes 11 and 12 of the bush 8 and the drive shaft 6, respectively. The distance across which the pin 15 and thus the sliding roller 4 is moved to and fro can be changed in a simple way by adjusting the bolts 9 and thus the angle between the axis 11 of the bush 8 and the axis 12 of the shaft 6.
Fig. 2 shows the possibility that the oscillating member 14 is circular and is coupled to the shaft 3 of a sliding roller 4 in a number of places.
It will be obvious, that only one possible embodiment of the invention of a device according to the invention has been illustrated in the drawing and described above and that many changes can be made without leaving the inventive idea as indicated in the accompanying claims.

Claims

Device for use in a printing machine for axially reciprocating one or more rotatingly driven sliding rollers (4), said device having a drive shaft (6) supported by the frame (1, 2) of the printing machine, which can be driven at a speed related to the speed of the rollers of the printing machine, a pivot pin (7) extending square to the axis (12) of the drive shaft (6) being mounted in said drive shaft, a bush (8) being pivotally supported on said pin (7), means (9, 10) being provided for fixing the bush (8) in a certain position in relation to the drive shaft (6) in such a way that the axis (11) of the bush (8) can enclose an angle with the axis (12) of the drive shaft (6), in which said bush (8) rotatingly mounts an oscillating member (14) which at a distance from the axis (11) of the bush (8) is coupled to the shaft of at least one sliding roller (4) to be operated by it, in such a way that when the axis (11) of the bush (8) encloses an angle with the axis (12) of the drive shaft (6), the sliding roller (4) performs a reciprocating motion, characterized in that through a coupling rod (15) being substantially parallel to the drive shaft (6) and the sliding roller (4), the oscillating member (14) is coupled to an arm (16) rotatingly connected to the shaft (3) of the sliding roller (4), said arm extending substantially square to the axis of the sliding roller, in which the coupling rod (15) can perform a certain pivoting movement in relation to the oscillating member (14) and the arm (16), and the rotational movement of the sliding rollers can take place indepently from one another.