Gripper for page-type printing material

Abstract

The invention relates to a gripper for printing materials in the form of pages, having a body made of fiber-reinforced plastic, characterized in that the body (2) has a layer structure (20, 41), the layers (20, 41) being non-detachably connected to one another and at least one continuous fiber (30, 30a) being provided in each of a plurality of the layers (20, 41). The invention makes it possible to produce in an advantageous manner a grabber of a lightweight structure with the necessary strength and with the necessary tribological properties. The invention is used, for example, in a sheet printing press.

Description

Technical Field

[0001] The invention relates to a gripper for sheet-shaped printing materials having the features of the preamble of claim 1.

[0002] The invention belongs to the technical field of the printing industry and in particular to the field of holding and conveying flat sheet-shaped substrates, preferably paper, cardboard, paperboard, plastic, metal, label material or composite materials, by means of manipulable grippers. Background Art

[0003] Printing presses that process sheets usually have conveyor rollers for the sheets of printing material, which conveyor rollers include a gripper system with a plurality of manipulable grippers (e.g., two groups of approximately 20 grippers per roller). In the outfeed of such machines, gripper bridges guided on chains are also used, which also have a plurality of manipulable grippers. Such grippers are usually made of metal (e.g., in the form of brass castings) and therefore have a correspondingly high weight. The weight of the grippers can be reduced by using plastics (keyword being lightweight design), but this can negatively affect the strength and tribological properties of the grippers.

[0004] Document DE2703843A1 discloses a sheet holding element having a body made of glass-fiber reinforced thermoplastic material. However, there is no description of the fiber length, nor of the structure and manufacture of the body.

[0005] Thus, it is already known to reinforce components made of plastic, in particular grippers, with fibers. Furthermore, it is also known to additively produce (“3D print”) the components themselves from plastic, and to use “endless fibers”, that is, to use fibers that are unwound from a spool and embedded in the plastic during the additive production of the component. Corresponding 3D printers are already available on the market. Summary of the invention

[0006] Against this background, the object of the present invention is to provide a technical solution which is improved compared to the prior art and which in particular allows the production of a gripper with the required strength and the required tribological properties in a lightweight design.

[0007] The invention achieves this object by means of a gripper according to claim 1 .

[0008] Advantageous and therefore preferred developments of the invention emerge from the dependent claims as well as the description and the drawings.

[0009] The gripper for sheet-shaped printing materials according to the present invention has a fiber-reinforced plastic ( The invention relates to a body of a textile material, characterized in that the body has a layer structure (Schichtaufbau), the layers of which are inseparable from one another and in which at least one continuous fiber or continuous fiber ( Faser).

[0010] The invention advantageously enables the production of a gripper in a lightweight design having the required strength and the required tribological properties.

[0011] By providing (in particular embedding) fibers (preferably carbon fibers), the weight of the gripper can be advantageously significantly reduced (compared to a gripper made of metal) while maintaining the same or even improved strength. By reducing the weight of the individual grippers, it is also advantageously possible to reduce the weight of the entire gripper assembly having a plurality of grippers.

[0012] The weight of a single gripper can be reduced by about 80% according to the present invention, and the weight of a gripper assembly can be reduced by about 50%.

[0013] The feature “the layers are inseparably connected to one another” is to be understood as meaning that detachment of the layers from one another would lead to destruction of the body.

[0014] The feature "at least one continuous fiber is provided in each of a plurality of these layers" is to be understood as meaning that the body has at least one dimension, for example a dimension in the circumferential direction for a substantially annular body. The length of a continuous fiber substantially corresponds to the length of this dimension or is longer, i.e., for example, the length of the dimension in the circumferential direction. Preferably, it exceeds 90% or 95%. Insignificant differences may arise, for example, from cutting off a fiber from a (preferably "endless", for example wound) fiber supply. The length of a continuous fiber can also be a multiple of this dimension, for example, when such fibers are arranged multiple times in the circumferential direction.

[0015] The invention is used, for example, in sheet-fed printing presses or post-processing machines in the printing industry.

[0016] The following describes preferred developments of the present invention (hereinafter referred to as developments). These developments can also be combined with one another as long as there are no technical exclusions.

[0017] An extension can be characterized in that the layers are additively manufactured, preferably printed with the aid of a liquid or pasty material. An extension can be characterized in that the layers are made of plastic. An extension can be characterized in that the layers are composed of plastic tracks (Kunststoffbahn) that are adjacent to each other (for example, generated with the aid of a nozzle). An extension can be characterized in that the layers are fused to each other. An extension can be characterized in that the layers are oriented transversely to the longitudinal axis of the body, in particular for a substantially annular body. An extension can be characterized in that there are more than 100 layers and more than 100 continuous fibers.

[0018] One embodiment can be characterized in that the fibers are arranged in a plane. One embodiment can be characterized in that the plane is parallel to the plane of the layer. One embodiment can be characterized in that the fibers are embedded in the plastic.

[0019] One development can be characterized in that the body has a central notch, for example, of essentially annular design. One development can be characterized in that this opening or notch (Aussparung) is used to mount the body on a gripper rod. One development can be characterized in that the fibers are arranged in a circumferential direction in a layer around the notch. One development can be characterized in that the fibers have a fiber start point and a fiber end point, and the fiber end point is arranged close to the fiber start point; preferably as close as the production process allows. One development can be characterized in that those fiber start points and those fiber end points in adjacent layers are arranged offset with respect to each other in the circumferential direction. By providing this offset (Versatz), the strength of the body can be further improved in an advantageous manner.

[0020] One development can be characterized in that the body comprises at least one recess pointing radially inwards toward the central recess for receiving a bearing.

[0021] One development can be characterized in that the fibers are carbon fibers, aramid fibers or glass fibers.

[0022] One development can be characterized in that the body has at least one groove. One development can be characterized in that a sliding bearing or a rolling bearing is arranged in the groove. These bearings can be made of brass; alternatively, they can also be made of plastic like the body.

[0023] The features and feature combinations disclosed in the above-mentioned technical fields, inventions and developments as well as in the following exemplary embodiments—in any combination with one another—represent further advantageous developments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings show preferred embodiments of the present invention and its developments. In the accompanying drawings, corresponding features are indicated by the same reference numerals.

[0025] Figure 1 A preferred embodiment of a gripper according to the invention is shown in a perspective view.

[0026] Figure 2 A preferred embodiment of a gripper according to the invention is shown in cross-section. DETAILED DESCRIPTION

[0027] exist Figure 1 1 shows a (lightweight) gripper 1 according to the invention or its body 2. The gripper 1 (preferably together with a gripper support (Greiferauflage) not shown) is used to preferably hold a sheet consisting of a printing material 10 (shown only in sections and in dashed lines) during the transport of the sheet. The body 2 comprises an annular body section 2a, on which a plurality of radially protruding body sections 2b are arranged. On one of these protruding body sections 2b, for example, a gripper finger 8 (shown in shading) can be mounted, which is preferably made of metal. The body 2 also comprises a central notch 3 in the direction of the longitudinal axis 4 of the body 2 and two inwardly directed circumferential grooves 5. By means of the notch 3, the body 2 can be received on a gripper rod 11 (shown together in symbolic form and in dashed lines) of a gripper device 12 of a printing press 13. In the grooves 5, a bearing 7, in particular a bearing ring 7 (shown in shading), can be arranged respectively, wherein the bearing ring 7 is preferably made of brass or bronze. Alternatively, the bearing ring can be made of a plastic with corresponding tribological property requirements. Furthermore, a rolling bearing can also be arranged alternatively.

[0028] exist Figure 2 In the figure, the (same) layer 20 of the body 2 is shown on the left, middle and right sides respectively. The middle view shows the layer 20 or layer plane 41, which is arranged perpendicular to the longitudinal axis 4 of the body 2 and shows the fibers 30 embedded therein, preferably made of carbon. The right view only shows the fibers 30 for the sake of clarity. Those lines shown in the middle view that do not correspond to the lines in the right view (i.e. the fibers 30) represent the production-related traces 21 of the body 2 made of plastic. These traces 21 are produced during additive manufacturing and fuse to each other. For the hardened body 2, the traces and layers can no longer be separated from each other (without destruction). It can be seen that the body 2 is formed radially inwardly and radially outwardly by two exemplary plastic traces. It can also be seen that the body is formed by meandering plastic traces in its interior. The left view shows the same body 2 as the middle view, but with an additional support structure 6 (or traces 22 of the support structure). The support structure 6 is removed from the body 2 after production; the support structure 6 is only an auxiliary structure for additive manufacturing.

[0029] As can be seen in the right side view, four exemplary fibers 30 are arranged in a layer plane 41. These fibers 30 form a fiber plane 40. One of the fibers is a continuous fiber 30a that is arranged in a circumferential direction with reference to the longitudinal axis 4 of the body 2. The other three fibers are helically extending fibers 30b. Each fiber 30 has a fiber starting point 31 and a fiber end point 32. The fiber starting point 31 and the fiber end point 32 of the continuous fiber 30a are arranged adjacent to each other in the layer plane 4; the distance between the fiber starting point 31 and the fiber end point 32 in the circumferential direction is given by the production process and is preferably kept to a minimum. In another layer plane 41 (not shown) located below or above the layer plane 4, the fiber starting point 31 and the fiber end point 32 are arranged offset 34 in the circumferential direction relative to the fiber starting point 31 and the fiber end point 32 in the above-mentioned layer plane 4. This offset 34 is Figure 1 In the figure, two (only shown in sections) surrounding fibers 30a located in different layers / planes are indicated schematically.

[0030] For manufacturing the body 2, a so-called 3D printer can be used. Such a 3D printer preferably comprises a printing head with two nozzles: one nozzle prints the plastic in the form of a track, and the other nozzle applies "endless" fibers. Here, a knife is used to cut the fiber bundle after it has been applied.

[0031] Reference numerals list

[0032] 1 Grabber

[0033] 2 body

[0034] 2a Body section, annular

[0035] 2b Body section, protruding

[0036] 3 Central notch

[0037] 4 Vertical axis

[0038] 5One or more grooves

[0039] 6 Support structure

[0040] 7 Bearings, especially one or more bearing rings

[0041] 8 Grabber fingers

[0042] 10 Printing materials

[0043] 11 Grabber rod

[0044] 12 Grabber device

[0045] 13 Printing Press

[0046] 20One or more layers

[0047] 21 One or more traces of the body

[0048] 22 One or more traces of the support structure

[0049] 30 or more fibers

[0050] 30a Surround fiber

[0051] 30b Fiber

[0052] 31 Fiber starting point

[0053] 32 fiber end point

[0054] 33Circumferential direction

[0055] 34 staggered

[0056] 40 Fiber Plane

[0057] 41st floor plan

Claims

1. A gripper for sheet-shaped printing materials, the gripper having a body made of fiber-reinforced plastic, It is characterized in that The body (2) has a layer structure (20, 41), wherein the layers (20, 41) are non-detachably connected to one another and at least one continuous fiber (30, 30a) is provided in each of a plurality of the layers (20, 41).

2. The gripper according to claim 1, It is characterized in that These layers (20, 41) are manufactured in an additive manner.

3. The gripper according to claim 1, It is characterized in that The layers (20, 41) are oriented transversely to the longitudinal axis (4) of the body (2).

4. The gripper according to claim 1, It is characterized in that The fibers (30, 30a) are arranged in a plane (40).

5. Gripper according to one of the preceding claims, It is characterized in that The body (2) has a central notch (3).

6. The gripper according to claim 5, It is characterized in that The notch (3) is configured for mounting the body (2) on a grabber rod (11).

7. The gripper according to claim 5 or 6, It is characterized in that The fibers (30, 30a) are arranged in the layer (20) in a circumferential direction around the opening (3).

8. The gripper according to claim 7, It is characterized in that The fiber (30, 30a) has a fiber start point (31) and a fiber end point (32), and The fiber end point (32) is arranged close to the fiber start point (31).

9. The gripper according to claim 8, It is characterized in that The fiber starting points (31) and the fiber ending points (32) in adjacent layers (20, 40, 41) are arranged offset (34) relative to one another in the circumferential direction.

10. The gripper according to any one of the preceding claims 5 to 9, It is characterized in that The body (2) comprises at least one recess (5) directed radially inwards towards the central notch (3) for receiving a bearing (7).

11. Gripper according to one of the preceding claims, It is characterized in that The fiber (30) is carbon fiber, aramid fiber or glass fiber.

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