WO2008119598A1

WO2008119598A1 - Roller, particularly for controlling the gripper shaft on sheet-fed offset printing presses

Info

Publication number: WO2008119598A1
Application number: PCT/EP2008/052012
Authority: WO
Inventors: Markus Haasler
Original assignee: Schaeffler Kg
Priority date: 2007-03-30
Filing date: 2008-02-19
Publication date: 2008-10-09
Also published as: DE102007015422A1

Abstract

The invention relates to a roller (1) which is suitable for controlling the gripper shaft on sheet-fed offset printing presses and in which a plurality of rolling members (6, 7) that are disposed next to each other in several rows (2, 3, 4, 5) roll within several external raceways (8, 9, 10, 11) on the external surface (12) of an inner ring (13) and within several internal raceways (14, 15, 16, 17) on the inner surface (18) of a thick-walled outer ring (19). The external surface (20) of the outer ring (19) has a convex contour from a cross-sectional view and is used for directly rolling along a cylindrical opposite raceway. According to the invention, all rolling members (6, 7) of the roller (1) are designed as spherical rolls which have two faces that are symmetrically oblate at the axial end and extend parallel to each other, thus being characterized by a narrow style compared to conventional bearing balls while having the same load-bearing capacity such that the axial and radial dimensions of the roller (1) do not need to be modified even if the rolling members (6, 7) are disposed next to each other in four rows (2, 3, 4, 5).

Description

Name of the invention

Roller, in particular for gripper shaft control on sheet-fed offset printing machines

description

Field of the invention

The invention relates to a roller according to the preamble-forming features of claim 1, and they are particularly advantageous in rollers for gripper shaft control on sheet-fed offset printing machines or for control rollers in the folder of roll offset printing machines applicable.

Background of the invention

Track rollers are proven, highly durable and versatile machine elements that are used in a wide variety of applications. The most common embodiments are support rollers, cam rollers and standard rollers, which differ mostly by different rolling element sets and have either a conventional inner ring or a roller journal. However, all embodiments are characterized mainly by their thick-walled outer rings, by which they are particularly well suited for direct rolling on cams or other flat or cylindrical mating counter tracks. The outer lateral surface of this outer ring usually has a convex contour in cross-section, in order to reduce the edge load and the wear of the mating track during tilting of the roller. Since rollers are suitable for absorbing high radial loads as well as axial forces in both directions, typical applications of rollers are, for example, the gripper shaft control on sheet offset printing machines or as control rollers in the folding unit of web offset printing machines or also their use in cam gears, Conveying systems or linear guidance systems. Such rollers are known inter alia by the published by the applicant Catalog "Rolling" January 2006 and are shown and described on pages 822 to 892 in the aforementioned embodiments as support rollers, cam rollers and standard rollers.

The support rollers shown are formed by ready-to-install needle or cylindrical roller bearings with particularly thick-walled outer ring whose rolling elements are formed by full needle or cage-guided needle rims or by full complement or cage-guided single or double row cylindrical roller rings. The support rollers can be designed sealed with or without axial guidance of the outer ring and open or by lip, gap or labyrinth seals and are mounted with or without inner ring on axles.

By contrast, the illustrated cam rollers essentially correspond to the support rollers with axial guidance, but instead of the inner ring have a solid roller journal with a fastening thread and a thrust washer. Even with cam rollers, the rolling elements are formed either by vollnadelige or cage-guided needle rims or by full complement or cage-guided single or double row cylindrical roller rings, which are sealed to the outside by lip, gap or labyrinth seals against dirt and spray.

As a standard rollers finally rollers are still shown, the same in their construction single or multi-row groove or angular contact bearings and essentially consist of an outer ring an inner ring and a plurality of mostly two ball rings side by side arranged bearing balls, in two outer raceways Roll off the outer lateral surface of the inner ring or a roller pin and in two inner raceways on the inner circumferential surface of the thick-walled outer ring. The ball and cage assemblies are guided in plastic cages and sealed to the outside by lip or gap seals against dirt and spray. A disadvantage of the said support and cam rollers, it has been found that trained as bearing needles or cylindrical rollers have a line contact with their careers, the cause of a relatively high friction torque and, together with the high flexing of the filled lubricant for increased heat is in the caster. In continuous operation, the increased heat development in the roller can lead to a thermal expansion of their individual parts, through which the friction torque in the roller even higher and their life is severely limited. Likewise, results from the line contact trained as bearing needles or cylindrical rollers rolling elements to their careers in connection with high operating speeds and the centrifugal forces acting an unfavorable distribution of lubricant in the roller through which there is insufficient lubrication between the rolling elements and their raceways and a further increase of Reibmomentes can come. In addition, the previous sealing concepts both on support and cam rollers and on standard rollers have not proven sufficient to centrifugal force occurring at high operating speeds accumulating the lubricant within the rollers on the inside of its outer ring and the consequent leakage of the lubricant to effectively avoid the seals passing out of the roller. In the case of standard castors, it has also been shown that they reach the limits of their load capacity at high radial and axial loads and at high operating speeds and that they have an extremely shortened service life due to the occurrence of lubricant deficiencies and bearing overheating. An obvious measure to avoid such premature caster failures would be to increase their carrying capacity by larger-sized rolling elements or by arranging additional rows of rolling stock, however, such measures usually always at the expense of the radial and axial dimensions of the roller and usually require extensive changes in Anschlußkon - construction. Object of the invention

Based on the stated disadvantages of the solutions of the known

It is therefore an object of the invention to conceive a roller, in particular for gripper shaft control, on sheet-fed offset printing presses which, given the same or approximately the same axial and radial dimensions as known rollers, have a higher load capacity, a lower frictional torque, a more favorable Has lubricant distribution and a longer service life and in which a centrifugally induced leakage of the lubricant from the seals is effectively avoided.

Description of the invention

According to the invention this object is achieved in a roller with the features of the preamble of claim 1 such that all rolling elements of the roller are formed as ball rollers, each having two axialsei- tig symmetrically flattened from their basic spherical shape, mutually parallel end faces.

The invention is thus based on the finding that it is already possible by replacing the previously trained as bearing balls or needles or as cylindrical rollers against trained as ball rollers and rolling elements adapted thereto track formation in the roller, while reducing the friction torque the Number of rolling elements and thus increase the carrying capacity of a roller so that it is also suitable for higher radial loads at high operating speeds, with no changes in the axial and radial dimensions of such a roller are required by the axially flattened and thus narrow design of the rolling elements. Preferred embodiments and advantageous developments of the inventively designed roller are described in the subclaims.

Thereafter, it is according to the claims 2 and 3 in accordance with the invention provided roller provided that it preferably has four rows formed as ball rollers rolling elements, of which the two inner rows are formed with an identical pitch circle diameter, which is smaller than the also identical pitch circle diameter of the two outer rows. In addition, while the diameter of the ball basic shape of the rolling elements of the two outer rows compared to the diameter of the rolling elements of the two inner rows is larger, so that in each case an outer row and the adjacently arranged inner row of rolling elements a first and a second row pair, each with different Wälzkörper- and pitch circle diameters. Alternatively, it would also be possible to form the ball rollers of all rows with the same diameter of the ball basic shape at different pitch diameters between the inner and the outer rows of rolling elements. Likewise, it would be conceivable to equip the roller depending on the respective required load ratings with less or more than four rows trained as ball rolling elements with the same or different ball basic diameters. Regardless, however, it is advantageous to additionally form the ball rollers on the edge parts of their treads or the edge parts of their raceways in the inner and outer ring with an expiring logarithmic profile to counteract occurring edge stresses between the ball rollers and their raceways.

Based on the above-described embodiment, the inventively designed roller according to claims 4 and 5 further characterized by the fact that the adjacent rolling elements of both pairs of rows are each arranged on a common axis of rotation and parallel to each other inclined Druckwinkelachsen and both pairs of rows of rolling elements in O Arrangement against each other are hired. The rolling elements of each pair of rows are preferably guided in each case in a common, designed as a plastic cage cage bearing cage such that each arranged on a common axis of rotation rolling elements are arranged in a common cage window with their facing side surfaces adjacent to each other and thus in an advantageous One way one way lead each other. In addition, it has proven to be particularly advantageous kinematically, if the diameter and widths of the adjacent rolling elements of both rows are each dimensioned such that all the rolling elements tangent to their outer contours Hüllkegel with their conical tips exactly at the intersection of the common axis of rotation of these rolling elements with the Rotation axis of the axial angular contact bearings are arranged. This Hüllkegel bearing kinematics, which is known per se from tapered roller bearings, represents an optimum for angular contact bearings of all types with regard to bearing load capacity, wear reduction and service life, and moreover, in the specific case, causes the respective adjacent ball rollers of two adjacent rows to roll synchronously with one another or that at different relative speeds between these ball rollers, the friction occurring is reduced.

An alternative embodiment of a roller according to the invention designed according to claim 6 beyond, the roller only with three rows trained as ball rollers rolling elements, all of which have an identical diameter of the ball base and the same pitch circle diameter. The rolling elements formed in this way are arranged on mutually perpendicular pressure angle axes and are guided in rows in individual, preferably designed as Kunststoffschnappkäfige bearing cages. Such an embodiment has proven to be particularly advantageous for applications in which the roller at high operating speeds higher radial loads but lower axial forces, such as in conveyor systems or linear guide systems, is exposed. Depending on the respective required load ratings, however, it is also possible in such trained rollers, these trained with less or more than three rows designed as ball rollers rolling with the same ball basic diameters.

Regardless of its embodiment, it is according to claims 7 and 8 nor an expedient development of the inventively designed roller that axially adjacent to the two outer rows of rolling elements respectively arranged as a reinforced lip seal seal is arranged, with which the formed as a lubricant reservoir space between the outer ring and the inner ring or the roller journal of the roller is sealed. These lip seals are each fixed in position in a hard-turned annular groove in the inner circumferential surface of the outer ring and are supported by one or more elastic sealing lips in each case in a Umlaufnut or on another surface in / on the outer circumferential surface of the inner ring or the roller journal of the roller. Such, known per se lip seals are here by the use of ball rollers as rolling elements for the roller and the associated reduced axial space requirements of Wälzkörpersatzes particularly advantageous applicable and wear in comparison to the previously mostly used gap or labyrinth seals essential to optimize the sealing effect in the space between the inner ring and the outer ring of the roller penetrating impurities and moisture at. In addition, the hard turning of the annular grooves for the seal attachment causes an increase in the accuracy of the seal seat, through which a centrifugal force due to leakage of the lubricant through the seals through the roller at high operating speeds is effectively avoided.

Finally, it is proposed as an advantageous embodiment of the inventively embodied rolling bearing by claim 9 that both the outer surface of the outer ring and the running surfaces of the rolling elements or their outer and inner races in the outer ring or inner ring or roller journal have a wear-reducing coating. To be particularly suitable a wear-resistant layer of Triondur ^® or Balinit ^® or a thin layer chromium has proved, because each of these coatings protecting a up to 80% lower coefficient of friction compared to a pairing has steel-steel dry, so that both the utility life of the Roller in relation to the mating track and the service life of the rolling element set of the roller can be significantly increased. In summary, the inventively designed roller thus compared to the rollers known from the prior art has the advantage that it has a higher load capacity and a lower frictional torque due to the use of multiple rows of ball rollers as rolling elements with the same or approximately the same axial and radial dimensions as known rollers. In addition, the ball rollers allow by their point contact to the raceways a more favorable distribution of lubricant in the roller and their reduced Axialbauraum the formation of an enlarged lubricant deposits and the use of optimized seals through which a centrifugal force due to leakage of the lubricant from the roller is effectively avoided. This and additional wear protection layers on the outer surface of the outer ring and on the running surfaces of the rolling elements or on the outer and inner races in the outer ring or inner ring or roller journal, the service life of the roller can be significantly increased.

Brief description of the drawings

The roller according to the invention is explained in more detail below in two preferred embodiments with reference to the accompanying drawings. Showing:

1 shows an enlarged cross section through a first embodiment of an inventively designed roller;

2 shows an enlarged cross section through a second embodiment of an inventively designed roller.

Detailed description of the drawings

From Figure 1 is clearly a suitable for the gripper shaft control of a sheet-fed offset printing machine roller 1, in which a plurality in four rows 2, 3, 4, 5 juxtaposed rolling elements 6, 7 in four outer races 8, 9, 10, 11 at the outer circumferential surface 12 of an inner ring 13 as well as in four inner raceways 14, 15, 16, 17 roll on the inner circumferential surface 18 of a thick-walled outer ring 19, the outer lateral surface 20 has a convex contour in cross-section and is provided for direct rolling on a cylindrical mating track. All rolling elements 6, 7 of this roller 1 are inventively designed as ball rollers, each having two axial side symmetrically flattened from its basic spherical shape, parallel to each other arranged faces and thus characterized over conventional bearing balls with the same load capacity by such a narrow design that despite the in four rows 2, 3, 4, 5 juxtaposed rolling elements 6, 7 no changes in the axial and radial dimensions of the roller 1 are necessary.

Furthermore, it can be seen in Figure 1 that of the four rows 2, 3, 4, 5 formed as ball rollers rolling elements 6, 7, the two inner rows 3, 4 are formed with an identical pitch diameter, which is smaller than the also identical pitch circle diameter of the two outer rows 2, 5 and that at the same time the diameter of the ball basic shape of the rolling elements 6 of the two outer rows 2, 5 is greater than the diameter of the rolling elements 7 of the two inner rows 3, 4 is formed.

A special feature of the roller 1 shown in Figure 1 is that each form an outer row 2, 5 and the adjacent inner row 3, 4, a first and a second row pair 21, 22 and the adjacent rolling elements 6, 7 of these two row pairs 21st , 22 each on a common axis of rotation 23, 24 and on mutually parallel oblique pressure angle axes 25, 26, 27, 28 are arranged. Both pairs of rows 21, 22 of the rolling elements 6, 7 are in O arrangement against each other employed and are each guided in a common, designed as a plastic cage cage bearing cage 29, 30 such that each arranged on a common axis of rotation 23, 24 rolling elements , 7 are arranged in a common cage window and one another mutually lead or that the adjacent ball rollers of two adjacent rows 2, 3 and 4, 5 synchronously roll to each other. In contrast, FIG. 2 shows a roller 1 'which is particularly suitable for conveyor systems or linear guide systems, in which, unlike roller 1 described above, a multiplicity of rolling elements 6 arranged side by side in three rows 2, 3, 4 in three outer races 8, 9, 10 on the outer circumferential surface 12 of an inner ring 13 and in three inner races 14, 15, 16 roll on the inner circumferential surface 18 of a thick-walled outer ring 19, whose outer lateral surface 20 also has a convex contour in cross-section. The rolling elements 6 are also formed as ball rollers, each having two axially symmetrical flattened from its basic spherical shape, parallel to each other arranged end faces and rows in three in individual, designed as Kunststoffschnappkäfige bearing cages 29, 30, 31 out. Clearly visible, the rolling elements 6 are also formed with an identical diameter of the ball basic shape and with the same pitch circle diameter and arranged parallel to each other vertically running Druckwinkelachsen 25, 26, 27, so that they can be loaded at high operating speeds and lower axial forces with higher radial forces ,

Finally, it can still be seen in FIGS. 1 and 2 that in both shown embodiments of the roller 1, 1 'axially adjacent to the two outer rows 2 and 5 or 2 and 4 of the rolling elements 6 there is a respective reinforced lip seal 32, 33 a trained seal is arranged, with which the trained as a lubricant depot, unspecified gap between the outer ring 19 and the inner ring 13 of the roller 1, 1 'is sealed off. This, by the use of ball rollers as rolling elements 6, 7 and the associated reduced axial space requirements of Wälzkörpersatzes space-optimized applicable lip seals 32, 33 are clearly visible each fixed in position in a hard-turned annular groove 34, 35 in the inner circumferential surface 18 of the outer ring 19 and based sliding over an elastic sealing lip in each case a circumferential groove 36, 37 in the outer circumferential surface 20 of the inner ring 13 of the roller 1, 1 'from. In addition, both the outer circumferential surface 20 of the outer ring 19 and the outer and inner races 8, 9, 10, 11 and 14, 15, 16, 17 in the outer ring 19 and in the inner ring 13 a wear-reducing coating of Triondur ^® , in order to increase the service life of the roller 1, 1 'on.

LIST OF REFERENCE NUMBERS

i, r roller 19 outer surface of 19

1 row of 6 20 row pairs of 2 and 3

2 row of 7 or 6 21 row pairs of 4 and 5

3 row of 7 or 6 22 rotation axis of 21

4 row of 6 23 rotation axis of 22

5 rolling elements 24 pressure angle axis of 2

6 rolling elements 25 pressure angle axis of 3

7 outer raceway in 12 26 pressure angle axis of 4

8 outer race in 12 27 pressure angle axis of 5

9 outer raceway in 12 28 bearing cage of 21 and 2 respectively

10 outer raceway in 12 29 bearing cage of 22 and 3 respectively

11 outer lateral surface of 13 30 bearing cage of 4

12 inner ring of 1, 1 '31 lip seal

13 inner race in 18 32 lip seal

14 inner race in 18 33 ring groove for 32

15 inner raceway in 18 34 annular groove for 33

16 inner race in 18 35 circumferential groove for 32

17 inner circumferential surface of 19 36 circumferential groove for 33

18 outer ring of 1, 1 '

Claims

claims

1. roller (1), in particular for gripper shaft control on sheet-fed offset printing machines, in which a plurality in several rows (2, 3, 4, 5) juxtaposed rolling elements (6, 7) in a plurality of outer races (8, 9, 10 , 11) on the outer circumferential surface (12) of an inner ring (13) or roller journal and in several inner raceways (14, 15, 16, 17) on the inner circumferential surface (18) of a thick-walled outer ring (19) roll, the outer circumferential surface (20 ) has a cross-sectionally flat or convex contour and is provided for direct rolling on a flat or cylindrical mating track, characterized in that all the rolling elements (6, 7) of the roller (1) are designed as ball rollers, each two axially symmetrical from have their spherical basic shape flattened, mutually parallel end faces.

2. Roller (1) according to claim 1, characterized in that it preferably four rows (2, 3, 4, 5) designed as ball rollers rolling elements (6, 7), of which the two inner rows (3, 4) an identical pitch circle diameter are formed, which is smaller than the also identi see pitch circle diameter of the two outer rows (2, 5).

3. roller (1) according to claim 2, characterized in that the diameter of the ball basic shape of the rolling elements (6) of the two outer rows (2, 5) relative to the diameter of the rolling elements (7) of the two inner rows (3, 4) larger is formed and in each case an outer row (2, 5) and the adjacent inner row (3, 4) form a first and a second row pair (21, 22).

4. roller (1) according to claim 3, characterized in that the adjacent rolling elements (6, 7) of both pairs of rows (21, 22) each on a common axis of rotation (23, 24) and on parallel to each other obliquely extending Druckwinkelachsen (25 , 26, 27, 28) are arranged and both pairs of rows (21, 22) of the rolling elements (6, 7) are set in O arrangement against each other.

5. roller (1) according to claim 4, characterized in that the Wälz- body (6, 7) of each row pair (21, 22) preferably in a common, designed as a plastic cage cage bearing cage (29, 30) are guided and thereby each arranged on a common axis of rotation (23, 24) rolling elements (6, 7) are arranged on one side mutually leader in a common cage window.

6. roller (1 ') according to claim 1, characterized in that it preferably three in individual bearing cages (29, 30, 31) guided rows (2, 3, 4) designed as ball rollers rolling elements (6) having an identical Diameter of the ball base shape and formed with the same pitch circle diameter and on parallel to each other perpendicular pressure angle axes (25, 26, 27) are arranged.

7. roller (1, 1 ') according to claim 5 and 6, characterized in that axially adjacent to the two outer rows (2, 5 and 4) of the rolling elements (6) each as a reinforced lip seal (32, 33) formed seal is arranged, with which the trained as a lubricant depot space between the outer ring (19) and the inner ring (13) or shaft journal of the roller (1, 1 ') is sealed.

8. roller (1, 1 ') according to claim 7, characterized in that the lip seals (32, 33) in each case in a hard-turned annular groove (34, 35) in the inner circumferential surface (18) of the outer ring (19) are fixed in position and in one circumferential groove (36, 37) in the outer circumferential surface (20) of the inner ring (13) or roller journal of the roller (1, V) are supportingly supported by one or more elastic sealing lips.

9. roller (1, 1 ') according to claim 8, characterized in that both the outer circumferential surface (20) of the outer ring (19) and the running surfaces the rolling elements (6, 7) or their outer and inner races (8, 9, 10, 11 and 14, 15, 16, 17) in the outer ring (19) or in the inner ring (13) or in the roller journal a wear-reducing coating, for example from Triangur or a thin-layer chrome plating.