JPS6250137A - Plate cylinder of printing press - Google Patents

Abstract

PURPOSE:To prevent the generation of a printing obstruction due to a shock-streak and to enable the correction of registering disorder, by supporting the shaft of a plate cylinder by a bearing mechanism consisting of a needle bearing and the spherical bearing combined with the outer periphery of the needle bearing. CONSTITUTION:The bearing gap (r) of a plate cylinder 10 and a rubber cylinder 12 is killed by the bearer of a bearer contact mechanism and the axis of an impression cylinder 13 is slightly downwardly displaced in a printing start state but, because shock load F is transmitted to the plate cylinder 10 through the bearer 18, the axial displacement of the rubber cylinder 12 is not generated so far as the axis of the plate cylinder does not vary. Contrarily, even in a printing finish state, no displacement is similarly generated. Therefore, the change in the peripheral speed between the rubber cylinder 12 and the plate cylinder 10 is not also generated. When cocking is generated for registering, relative sliding is generated between the spherical guide surfaces between the inner and outer wheels of a spherical bearing 23 and the center points thereof come to load acting points 31a, 31b and, therefore, these points come to the centers of rotation at the time of cocking to prevent abnormal application of load of to a needle bearing.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a plate cylinder for a printing press, which is characterized by a bearing mechanism for the plate cylinder shaft.

(Prior art) As shown in Fig. 8, the plate cylinder shaft bearing in a conventional printing press consists of a frame (4) supporting the plate cylinder shaft (1) using a needle bearing (2) and a thrust bearing (3). , a needle bearing type (shown on the drive side) equipped with a drive gear (5) and a left/right register adjustment device (6), and a ninth
As shown in the figure, the plate cylinder axis 0υ of plate cylinder O1 is attached to the frame (9).
The tapered low earrings are broadly divided into two types: the chimney low earring type (the illustration shows the operation side where the drive gear is not installed), which is supported by a tapered low earring (7), and is equipped with a retaining nut (l'r). The mold has load application points (11
α) (11α) is formed, so that the relative deviation of the plate cylinder αQ axis position can be adjusted around the load application point as shown in FIG.

In addition, in a sheet-fed offset printing press, as shown in Fig. 4.5, a claw device I provided on the intermediate cylinder and the impression cylinder During the conveyance process, the ink (h) is transferred from the printing cylinder (1G) to the printing paper (α) surface on the impression cylinder 03 via the blanket cylinder O2 to print. A drive gear that meshes with each other to transmit power is attached to the end of the drive side for winter use, and a pressure applying mechanism (eccentric bearing) is installed between the printing cylinder OI and the blanket cylinder (12 A similar mechanism is provided between the blanket cylinder fi3 and the impression cylinder 03 to apply printing pressure via the printing paper (al).

However, in the printing machine, the ink (α) is applied to the printing paper (α).
h) Shocking fluctuations in printing pressure occur depending on the presence or absence of printing paper at the beginning and end of the transfer, and the distance between the axes fluctuates due to the fluctuating load, and as shown in Figure 7, the taper roller Bearing (outer ring of force (7b) (7b) is
direction, a radial displacement δ occurs, and this displacement δ results in a change in the distance between the axes. ), as shown in Fig. 6, the displacement of the distance between the shafts becomes the displacement δ of the distance between the driving gears, and depending on the pressure angle of the gears, a gap α is generated between the gear tooth surfaces, or conversely, a negative gap is generated. This causes a relative phase shift between the gears. That is, due to shocking printing pressure fluctuations called printing pressure entry and printing pressure release, the blanket cylinder 02 and plate cylinder 0'
The circumferential speeds of the paper (α) 1: fluctuate rapidly, and these circumferential vibrations become a phenomenon in which the dot distribution becomes dense or coarse when subjected to an impact load. Dark and light lines appear, causing shock marks and printing problems.

Since the above-mentioned printing failure is caused by changes in the distance between the shafts of each cylinder, the rigidity of the bearings for winter should be increased as much as possible, and the dimensional change due to the thickness of the filter paper when printing paper is inserted into and taken out between the cylinders is due to rubber rather than bearing deflection. Basic countermeasures have been taken to absorb the damage by bending the rubber wrapped around the surface of the body, but this has its own limitations.

That is, the tapered roller bearing type shown in Figure 9.7 is
The gap between the frame hole and the tapered roller is pressed down) (lη
However, since the contact angle β is formed, the displacement of the outer ring (7h) in the X direction due to the impact load,
A displacement δ occurs in the radial direction, and in the needle bearing type shown in Fig. 8, the contact angle β is zero and there is no disadvantage of the tapered roller bearing, but it is necessary to eliminate the gap between the needle bearing and the frame hole. I can't.

Therefore, as shown in Figures 4 and 5, a general trap has a plate cylinder (1) and a rubber cylinder (1z) with a bearer (pillow) (l
A bearer contact mechanism (18, 18) is adopted in which the inter-axle gap (n) is concentrated in one direction by pressing the 0 marks against each other, and the impact load F is applied to the ear.
It is transmitted in the direction of the arrow through y08, and the change in the inter-cylinder distance between the plate cylinder C[(l and the blanket cylinder (1z) is prevented,
Between the rubber body circumference and the impression cylinder (131), printing paper of different paper thickness (
α) can be inserted, so the gap between the bodies can be kept constant, and the key f,
Without providing the bearer contact mechanism, the distance between the cylinders is mechanically changed so that the printing pressure is constant according to the paper thickness.

Furthermore, version r+! :1 (101 is the plate (15) with a thickness of 03, which is attached to the cylinder surface, and is attached to the plate (15).
is installed in the torsional direction as shown in Figures 2-3,
Normally, in color printing where four printing plates are used, misregistration (out of focus) occurs between each color, so in order to correct the misregistration, the plate tightening device installed on the plate cylinder must be manually operated by stopping the printing press. The most recent method has been to use an electric remote control to twist the plate cylinder during operation, in other words, to deliberately disturb the parallelism of the plate cylinder to the blanket cylinder by the amount of misregistration. In the case of the tapered roller bearing type shown in Fig. 9, the plate cylinder axis 01)
Since the load application points (llz) (11α) are formed on the operation side and the drive side of the plate cylinder flll, the plate cylinder fll is supported at two points, and it is possible to perform the twitching operation as shown in Fig. 3. In the needle earring type shown in the figure, since there is a width at the load application position, when the plate cylinder is knitted, the center of rotation of the bearing part is not determined, and an abnormal load is applied to the needle bearing, making it impossible to knit the plate cylinder.

(Problems with the prior art) In the above-mentioned conventional plate cylinder bearing mechanism, in the needle ear ring type, the load supporting position of the plate cylinder shaft has a width, so when the plate cylinder is knitted, the center of rotation of the bearing part is not determined and the needle earring type is used. There is a drawback that the abnormal load acts on the bearing, making it impossible to correct the misregistration by twisting.Also, with the tapered roller bearing type, it is possible to correct the misregistration by twisting, but the distance between the shafts changes due to the impact load. This method has drawbacks such as causing printing failures such as shock eyes and causing a decrease in printing accuracy.

(Objective of the Invention, Means for Solving Problems) The present invention was developed to address the above-mentioned problems, and includes a needle bearing and a spherical bearing combined on the outer periphery of the needle bearing. It is characterized by a structure in which the plate cylinder shaft is supported by a bearing mechanism, and by supporting the plate cylinder shaft by a bearing mechanism consisting of a needle bearing and a spherical bearing combined on the outer periphery of the The rigidity prevents center-to-axis distance fluctuations and circumferential speed fluctuations, significantly reducing the occurrence of printing failures caused by shock marks, and the spherical bearings enable the plate cylinder to be tilted to correct misregistration. It is an object of the present invention to provide a plate cylinder for a printing press which has significantly improved support performance, improved printing performance and operational reliability, and which solves the above-mentioned problems.

(Example) An example of the present invention is shown in FIGS. 1 to 5,
CI) shown in Fig. 1 is the plate cylinder shaft of the plate cylinder CIG, and the operating side and drive side of the nuclear plate cylinder shaft (21) are needle bearings (made by Co., Ltd.), and the needle is a spherical bearing assembled on the outer periphery of the ring. It is supported by a bearing mechanism (22, 23) consisting of (g) and (g).

The spherical bearing (c) has an inner ring with a thin spherical single-sided bushing (23α).
and an outer ring side spherical bush (23A), the spherical bushes (23α) and (23h) are capable of relative sliding on spherical contact surfaces, and the relative sliding causes the plate cylinder shaft 12
1) Load application points (31
α) (31h) is formed so that the plate cylinder can be rotated. In addition, an eccentric bearing (to) for locking is installed on the outer periphery of the outer ring side spherical bushing (236) of the spherical bearing (c) on the operation side, and a mark between the printing cylinder and the blanket cylinder is attached to the outer periphery of the eccentric bearing. An eccentric bearing cylinder for pressure adjustment is installed and disposed in the frame hole of the frame (7), and a thrust (ring 124) is provided on the outside of the bearing mechanism (22° 23). Further, the eccentric bearing (E) is connected to a cocking drive device (not shown) by an interlocking member (C), and the eccentric bearing sleeve is connected to a printing pressure adjustment device by an interlocking member (G), The device in the figure is a part of the left-right register adjustment device, and by moving it in the driving direction, the plate cylinder 0I can be moved via the thrust bearing Q4.

Further, on the drive side, an eccentric bearing G3 for adjusting printing pressure and a plate cylinder drive gear (to) are installed.

Furthermore, as shown in FIG. 4, a pillow (18) is provided on the plate cylinder α1.

(Function) The embodiment of the present invention has the above-described configuration, and as shown in FIGS. 4 and 5, the bearer α of the bearer contact mechanism
Bearing clearance (γ) of plate cylinder (In) and rubber cylinder (13) by barrel
is killed as shown in the figure, and when printing starts, the shaft core of the impression cylinder (+31) is not a bearer contact, so it is slightly displaced downward, but the shock load F of the blanket cylinder α2 is applied to the bearer α.
Since it is transmitted to the plate cylinder Ql via the mark, the axis of the rubber 11111θ2 will not shift unless the axis of the plate cylinder changes.

Next, the plate cylinder 01 receives an impact load F through the rear contact, but the bearing gap (γ) has already been closed by the rear contact, so that no axial displacement occurs. On the other hand, the condition of the printing path (
Similarly, even when printing is completed up to the end of the paper, no axis displacement occurs. Therefore, there is no change in peripheral speed between the blanket cylinder (1z) and the plate cylinder 0.

In addition, when the squaring is performed for registration as shown in Figure 3, relative sliding occurs between the spherical guide surfaces between the inner and outer rings of the spherical bearing, and the center point of this relative sliding is Since the load application points are (31α) and (31b), the load application points become the center of rotation during twisting, and an abnormal load is prevented from being applied to the needle bearing @.

(Effects of the Invention) As mentioned above, the present invention supports the plate cylinder axis Cυ with a bearing mechanism consisting of a needle ear ring and a spherical bearing (C) combined with the outer periphery of the needle bearing (C), so it has high rigidity. The needle earrings and spherical bearings effectively prevent center-to-axis distance fluctuations as well as circumferential speed fluctuations, significantly reducing the occurrence of printing failures caused by shock marks.The spherical bearings also enable the plate cylinder to be tilted, thereby reducing the pressure on the needle bearings. Abnormal loads can be prevented and misregistration can be corrected, and the support performance and operational reliability of the plate cylinder have been significantly improved.
Therefore, printing performance and reliability are also significantly improved.

Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited to such embodiments, and that various design modifications can be made without departing from the spirit of the present invention. .

[Brief explanation of drawings]

Fig. 1 is a longitudinal cross-sectional view showing one embodiment of the present invention, Figs. 2 and 3 are action explanatory views showing the locking operation, Fig. 4 is a front mechanical view showing the ara contact mechanism, and Fig. 5 is a Fig. 4 is an individual view, Fig. 6 is an explanatory diagram of circumferential speed fluctuations of a conventional drive gear, Fig. 7 is an explanatory diagram of interaxial distance fluctuations of a tapered roller earring, and Fig. 8 is a diagram of a bearing mechanism showing a conventional example. FIG. 9 is a longitudinal sectional view showing another conventional example. 10: Plate cylinder 21: Plate cylinder shaft 22: Neat 9
Le is Aling 23: Spherical bearing sub-agent Patent attorney Shige Okamoto 2 people outside the kiln Chaos 2 Figure 3 Figure 4 Scroll 5 Figure 6 Figure 7

Claims (1)

[Claims] A plate cylinder for a printing press, characterized in that a plate cylinder shaft is supported by a bearing mechanism consisting of a needle bearing and a spherical bearing combined with the outer periphery of the needle bearing.