JPH0457499B2 - - Google Patents

Description

BACKGROUND OF THE INVENTION The present invention relates to a cleaning device for a printing press, in particular a vacuum dry cleaning method for cleaning blanket cylinders in offset printing presses without interrupting or slowing down the operation of the press. It is related to the device.

Offset printing has become more dominant as a printing method in the newspaper publishing industry in recent years than letterpress printing. This is due in part to the improved sharpness of the printed image and the ability to print on paper materials with lower surface uniformity than that required for letterpress printing. moreover,
Another important factor in the popularity of offset printing is the low cost of printing plates used in offset printing machines.

Offset printing presses typically use a blanket cylinder, a rubber cylinder or rubber-coated cylinder for receiving the ink image from the printing plate. The ink image is then transferred onto the paper passing between two blanket cylinders or between a blanket cylinder and a printing cylinder. Continuous printing can be carried out by coating one or more printing plates along the circumference of the plate cylinder, which is designed to rotate in contact with the blanket cylinder.

In a blanket-to-blanket printing operation, a paper web passes between two blanket cylinders arranged so that one acts as a printing cylinder for the other, so that both sides of the paper web are printed simultaneously. will be held.

Continuous offset printing is adversely affected by so-called lint, which consists of dust and lint that escapes from the paper web and collects on the blanket cylinder. This lint degrades the quality of printed matter. The build-up of lint or ink on the blanket cylinder is a serious inconvenience and requires an undesirable outage of operation to clean it. This is particularly a problem in the newspaper industry where, as the cost of paper resources increases, less premium quality and therefore relatively high lint capacity newsprint is used.

Conventional vacuum systems for blanket cylinders have used wet vacuum systems to remove lint. In these systems, segments of the blanket cylinder are continuously immersed in a solvent to be cleaned. . Excess solvent is removed by a wiper having a vacuum header located close to its blade. Regarding this, for example,
See US Pat. No. 3,835,779 to Ross, et al. The present invention adopts a complete dry system to remove lint and other foreign substances,
Moreover, it does not require a lint catcher like conventional dry systems.

OBJECTS AND DEFINITIONS OF THE INVENTION One object of the invention is therefore to provide a device for cleaning a blanket cylinder during the printing process without interrupting the printing operation or consuming extra time. . This device improves the clarity and reproducibility of printed matter and almost eliminates machine stoppages. It also allows the use of relatively high lint capacity paper materials.

Another object of the present invention is to provide a device suitable for manufacture as an integral part of an offset printing press or as an accessory to fit into an existing printing press.

Yet another object of the present invention is to provide a vacuum blanket cleaner configured essentially as an automated mechanism that also allows adjustment by an operator.

Yet another object of the present invention is to provide an improved vacuum blanket cleaner that does not wear out the blanket cylinder.

Yet another object of the present invention is to provide an improved vacuum blanket cleaner that provides relatively long blanket life.

Yet another object of the present invention is to provide an improved vacuum blanket cleaner that operates without material loss.

Another object of the present invention is a plate (printing plate)
An object of the present invention is to provide an improved vacuum blanket cleaner having a relatively long life.

In the present invention, a device for cleaning a blanket cylinder of an offset printing press during printing operation includes a brush and a brush holder having the following structure. These brushes have air cylinders and are periodically urged toward the blanket cylinder based on the movement of a rotating arm connected to the brushes. The action of the brushes as the blanket cylinder rotates releases dust and lint from the blanket cylinder. The dust and lint are then drawn into a vacuum system that includes a housing surrounding the brushes, which are also segmented to provide brush sections that are to be separated from the cylinder when not in use. If selective segmentation is not possible, the brushes are laterally adjustable to accommodate webs of various sizes.

The frequency of automatic engagement and operation of the cylinders in the blanket cleaner of the present invention depends on various predetermined or monitored operating parameters, such as the length of press run time and the lint capacity of the printing paper. adjusted by the operator. The invention further provides for means provided within the housing to engage the blanket cylinder to perform both the lint release and vacuum system sealing functions.

The above-mentioned and other objects, configurations, and effects of the present invention will become clearer from the following description of preferred embodiments with reference to the drawings.

DESCRIPTION OF THE EMBODIMENTS Referring specifically to FIG. 1, a dry blanket cleaner according to one embodiment of the present invention is shown. The blanket cleaner, indicated generally at 20, includes a brush mechanism 22 consisting of at least one brush 24 and vacuum means (not shown).

The blanket cleaner according to this embodiment of the invention is mounted relative to the blanket cylinder 28 generally parallel to its cylinder axis. Blanket cleaner support brackets 30 are mounted to a press frame (not shown) slightly outside of either end of blanket cylinder 28. The blanket cleaner 20 has a rotating arm 34.
It is connected to the support bracket 30 by. These rotating arms 34 are attached to the blanket cleaner 2.
It is rotatably supported about a pin 36 for supporting and moving the 0.

Blanket cleaners generally pivot between two operating positions. Rotation of the arm 34 between these two positions is urged by a plurality of actuators 38 connected to the arm 34. The actuator should preferably be a pneumatic drive mechanism, but electrical or hydraulic drive mechanisms can be used if desired. In the first case (air drive), compressed air is conventionally supplied from a compressor room, whereas in the case of an electric or hydraulic drive, no special energy supply room is required. Blanket cleaner 20
is biased away from the blanket cylinder 28 in the first operating position, thereby allowing for example brush replacement, machine repair or service, or web replacement.

In the second operating position, the blanket cleaner 20 contacts the surface of the blanket cylinder 28. In this second position, the blanket cleaner performs a cleaning action, removing debris and other lint from the blanket cylinder.

The vacuum portion of the blanket cleaner 20 in one embodiment comprises a substantially U-shaped cross-section housing 40 extending along the length of the blanket cylinder and brush mechanism 22. Brush mechanism 22
is mounted inside a housing 40, which is secured to the pivot arm 34. The housing 40 holds the brush 2 held in the brush holder 25.
4, and this brush holder 25 is separably attached to the housing 40 by some convenient method so that it can be easily replaced as necessary. The brushes 24 are mounted in a pair of parallel rows as shown and have a relatively long life. However, it is clear that continued use will eventually require its replacement and repair.

Referring now to FIGS. 5 and 6, two alternative embodiments of brush mechanisms are shown.
In FIG. 5, the brush holder 62 is divided into sections so that each section can be lifted out of contact with the blanket cylinder being cleaned, if desired. That is,
Blanket cylinders for newspaper printing are generally 1/4
Since the web is formed for pages (the web is double width corresponding to the entire surface of the blanket or unit width corresponding to 1/2 side of the blanket), such division segmentation is required. If a unit width is used, the ink is delivered onto the cylinder surface without a web covering its entire surface. Segment the brush preferably into quadrants so that the brush in unused areas is lifted.

In the embodiment shown in FIG. 5, lifting of the segment is accomplished by manually operating the lever 64 of the lifting mechanism 65 toward the lowered position. This operation serves to lift the guide rod 66 connected to the brush holder 62 and separate that portion of the brush holder from the blanket cylinder. The brush mechanism can be divided into more parts if necessary to provide even greater flexibility to the cylinder. Generally, it is most useful to divide the brush mechanism into four parts. Additionally, the lifting of the brush mechanism portion may be accomplished by other effective means such as the illustrated manual operating means;
Or it can be carried out via automatic or semi-automatic means.

In commercial web printing, segmentation of brushes can be difficult to implement. This is because the amount of web used can vary widely. In such cases, the brush mechanism is laterally adjusted along the width of the blanket cylinder (see FIG. 6). In the embodiment of FIG. 6, brush holder 68 is slidably mounted along slot 72 in housing 70. In the embodiment of FIG. Locking means 74 are used to maintain the brush in the desired lateral position. In the embodiment of FIG. 6, a thumbscrew is used as the locking means for restraining the brush in the desired position. The brush is thus tailored to a particular application.

Blanket 28 is a material for the brush 24.
Various materials can be used as long as they do not easily damage the surface of the material. These materials include both natural and synthetic fibers. Brushes 94 are also mounted at an angle of up to 90 degrees from a tangent through the surface of the blanket cylinder to improve their ability to release and remove foreign matter such as lint from the cylinder circumference.

The housing 40 has side surfaces 46 and 48, respectively, parallel to a top surface 44 in the form of an inverted U-shaped channel. The housing 40 is mounted between the two pivot arms 34 and in the downward position.
Its opening face faces the blanket cylinder 28. The U-shaped channel housing 40 may be optionally mounted forward or rearward relative to the centerline of the blanket cylinder 28, as desired. For example, FIG. 4 shows an embodiment in which the brushes are mounted forward of the centerline of the blanket cylinder.

At least one brush 24 is attached to the housing 40
It is attached to the upper surface 44 through a brush holder 25 so as to be substantially parallel to both side surfaces 46 and 48, and when the cleaner is engaged and driven, the brush contacts the circumferential surface of the blanket cylinder and moves inside the housing. to release lint that has accumulated in the Optionally, a plurality of brushes may be arranged in rows and columns within the housing 40 to facilitate the release of lint from the surface of the blanket cylinder 28.

A flexible wiper 50 is disposed at the ends of the side walls 46 and 48 of the housing 40. The wiper 50 contacts the surface of the blanket cylinder 28 to provide a sealing surface for the blanket cylinder engaged by the blanket cleaner. These wipers 50 are also connected to the blanket cylinder 28
It also plays the role of releasing and discharging lint or the like from the surface of the body with lint or the like 52.

The released lint 52 is removed from the interior of the housing 40 by a suitable vacuum system. A vacuum generator (not shown) is connected to the housing 4 by a hose 56.
0 vacuum port 58. Lint 52
is delivered through hose 56 by vacuum means to be provided in a suitable equipment arrangement (not shown).

Referring now to FIGS. 2-4, the general operation of the blanket cleaner according to the embodiment of the present invention is shown. The web of printing material 60 passes between the opposingly rotating blanket cylinders 28 and is printed on both the front and back sides thereof. During this printing operation,
The lint 52 coming out of the web 60 accumulates on the surface of the blanket cylinder 28, and if left as it is, it will degrade the print quality of the printed matter.

In order to remove this litter from the surface of the blanket cylinder 28, the blanket cylinder 20, generally located at the top of the blanket cylinder 28, is pressed against the cylinder surface by suitable biasing means formed as an actuator 38. . Generally, it is not necessary for blanket cleaner 20 to be in continuous contact with blanket cylinder 28 during the entire printing operation. However, if a large amount of lint accumulates in a short period of time,
It is necessary to keep the blanket cleaner engaged with the cylinder surface throughout the printing operation. Under normal operating conditions, the blanket cleaner 20
is brought into pressure contact with the peripheral surface of the blanket cylinder periodically to clean the cylinder surface for a predetermined period of time.

The periodic operation of the blanket cleaner of the present invention is controlled by a conventional timing mechanism operating in conjunction with the rotation of the printing press or commands from an operator. In all cases, actuator operation will be performed when blanket cleaning is required.
The actuator 38 is operated to move the cleaner from the separated position (FIG. 3) to the engaged position (FIG. 2). In the engaged position,
Brushes 24 of brush mechanism 22 contact the surface of blanket cylinder 28. Brush 24 is used to sweep blanket cylinder 28;
After application to a predetermined number of rotations of the cylinder, actuator 38 is actuated to bring brush mechanism 22 to a disengaged position as shown in FIG.

During brush engagement, a predetermined amount of lint released and separated by the brushes 24 and to some extent by the wiper is suctioned away by the vacuum system;
This allows lint to be effectively removed from the blanket cylinder during printing operations.

The particular embodiments described above were chosen for their ease of instrumentation and adjustment; for example, the various operating parts are physically located on the blanket cylinder 28, making it easy to assemble and repair them. It can be easily operated. In a broader embodiment of the present invention, the use of brush mechanism 22 in conjunction with vacuum means 56 eliminates the need for a conventional lint capture mechanism, although other configurations may, of course, be employed. It can be eliminated.

As an example of a modification, the manner in which the actuator operates can be varied by using other sources of fluid motion or other timing mechanisms as described above. Also, the sequence of operating mechanisms can be varied as desired.

[Brief explanation of drawings]

FIG. 1 is a partial perspective view of a vacuum blanket cleaner system constructed in accordance with one embodiment of the present invention, FIG. 2 is a side view of the vacuum blanket cleaner system in an engaged position, and FIG. A side view showing the separated position of the vacuum blanket cleaner system; FIG. 4 is an enlarged partial sectional view of the brush mechanism;
FIG. 5 is a front sectional view of a brush mechanism with split segment brushes, and FIG. 6 is a front sectional view of a brush mechanism with laterally adjustable brushes. 20... Blanket cleaner, 22... Brush mechanism, 24... Brush, 25... Brush holder, 28... Blanket cylinder, 30... Support bracket, 34... Rotating arm, 36... Pin, 38 ... Actuator, 40 ... Housing, 44 ... Top surface, 46 ... Side surface, 50 ... Flexible wiper, 56 ... Hose, 58 ... Vacuum port.

Claims (1)

[Scope of Claims] 1. A dry vacuum device for removing dust and lint from a blanket cylinder of an offset printing press having at least one blanket cylinder rotating around a shaft mounted on a printing press frame. (a) a blanket cleaner support frame attached to the printing press frame adjacent to the blanket cylinder; (b) arm means movably connecting the support frame and the printing press frame; (c) brush housing means of substantially U-shaped cross section having a top wall extending along the length of the blanket cylinder and two side walls fixed to the movable arm means, the brush housing means being fixed to the movable arm means; (d) vacuum means cooperating with said housing to create a vacuum condition within said housing for a predetermined period of time; (e) vacuum means for moving said arm means away from said blanket cylinder; means for moving between a first position and a second position proximate said blanket cylinder; (f) mounted within said housing means, said arm means being placed in said second position; and a brush means adapted to engage with the blanket cylinder, the brush means releases dust and lint from the rotating blanket cylinder, and the vacuum means and the housing are free from dust. A dry vacuum device for a blanket cylinder, characterized in that the dust and lint can be removed and the dust and lint are prevented from escaping into the environment. 2. the housing protrudes from the housing and comes into contact with the blanket cylinder, thereby providing a sealing surface between the blanket cylinder and the housing when the brush means is engaged with the blanket cylinder; Apparatus according to claim 1, characterized in that it comprises means. 3. The brush means according to claim 2, wherein the brush means is divided into a plurality of parts, each of which is individually movable between the blanket cylinder engagement position and the separation position. Device. 4. Apparatus according to claim 3, characterized in that the brush means is divided into at least two parts. 5. The apparatus of claim 1, wherein said brush has a shorter alignment length than said housing means and is laterally adjustable along the length of said housing means. 6 is operably attached to the printing press body,
a brush mechanism including a brush movably supported between at least two positions, a first position separated from a blanket cylinder of the printing press and a second position in contact with the blanket cylinder; 1. A dry vacuum blanket cleaning device for cleaning a blanket cylinder of a printing press, characterized in that it is equipped with vacuum means for receiving dust and other foreign matter released by the blanket cylinder. 7. The brush means comprises a pair of linear brushes separably mounted within the U-shaped cross-section housing means.
The device described. 8. The apparatus of claim 1, wherein the means for moving the arm means is pneumatically driven. 9. Apparatus according to claim 1, characterized in that said brush means comprises at least one linear brush.