Air bearing stationary sheet guide mechanism for web printing apparatus

Abstract

The utility model discloses a paper guide mechanism of air floatation for rotary printing equipment, including the big angle of wrap greater than or equal to 150 degree big angle of wrap paper roll, big angle of wrap paper roll fixed setting on the frame, big angle of wrap paper roll has the working surface with the corresponding printing material, be equipped with a plurality of even distribution's air outlet on the working surface, air outlet is connected with outside gas source, when working, air outlet can blow out compressed gas, and printing material and big angle of wrap paper roll's working surface form the air film gap between. The utility model blows out compressed gas and the printing material surface with the air outlet, makes printing material lift up, and forms the air film gap between big angle of wrap paper roll, reduces the contact area between printing material and big angle of wrap paper roll, thereby in keeping the paper guide function while avoiding the influence that big angle of wrap paper roll's inertia produces to printing material.

Description

Technical Field

[0001] This utility model relates to the field of paper guiding in rotary printing equipment, and more particularly to an air-floating static paper guiding mechanism for rotary printing equipment. Background Technology

[0002] Paper guide rollers are common paper guiding components in rotary printing equipment, used to guide the substrate along a preset path through each printing unit. The substrate passes through multiple paper guide rollers sequentially, thus forming a complete paper path. The wrap angle of a paper guide roller refers to the central angle formed between the tangent direction of the substrate (such as paper) entering the roller and the tangent direction of its exit from the roller. Therefore, paper guide rollers in rotary printing equipment can be divided into small wrap angle paper guide rollers and large wrap angle paper guide rollers according to their contact range with the substrate. The larger the wrap angle, the longer the contact arc surface, and the greater the frictional force generated.

[0003] However, in intermittent printing or high-speed printing using low-grammage substrates, the large wrap-around paper rollers have a large inertia. When the printing press starts or stops or changes speed, this inertia will drive the roller to continue rotating, thus "dragging" the substrate out of place through its large friction force. This problem will directly cause misregistration. Summary of the Invention

[0004] This invention addresses the shortcomings of existing technologies by providing an air-floating stationary paper guide mechanism for rotary printing equipment. This mechanism utilizes the principle of air flotation to reduce the contact area between the substrate and the large-angle paper guide roller, thereby avoiding the influence of the inertia of the large-angle paper guide roller on the substrate.

[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution: an air-floating paper guiding mechanism for rotary printing equipment, comprising a large wrap angle paper guide roller with a wrap angle greater than or equal to 150°, the large wrap angle paper guide roller being fixedly mounted on the frame, the large wrap angle paper guide roller having a working surface corresponding to the substrate, the working surface being provided with a plurality of evenly distributed air outlets; the air outlets being connected to an external air source; during operation, the air outlets can blow out compressed gas, so that an air film gap is formed between the substrate and the working surface of the large wrap angle paper guide roller.

[0006] This invention blows compressed gas through the air hole onto the surface of the substrate, causing the substrate to lift up and forming an air film gap between it and the large-angle paper guide roller. This reduces the contact area between the substrate and the large-angle paper guide roller, thereby maintaining the paper guiding function while avoiding the influence of the inertia of the large-angle paper guide roller on the substrate.

[0007] Preferably, the air outlets are arranged axially on the surface of the hollow roller body in multiple rows, with the air outlets in adjacent rows staggered. This ensures that the gas is evenly distributed between the working surface and the substrate.

[0008] Preferably, the large wrapping angle paper feed roller includes a hollow roller body, a roller shaft, and an end cap, with both ends of the hollow roller body being fixedly connected to the roller shaft via the end caps.

[0009] Preferably, the inlet side of the connecting channel is equipped with a pneumatic connector, which is connected to an air source via a regulating valve. This allows for the adaptation of substrates of varying thicknesses. Attached Figure Description

[0010] Figure 1 This is a schematic diagram showing the arrangement of the large-angle paper feed roller and the small-angle paper feed roller along the moving path of the printing substrate.

[0011] Figure 2 This is the front view of this utility model.

[0012] Figure 3 This is a utility model Figure 2 A cross-sectional view along the AA direction.

[0013] The names of the body parts referred to by the numbers in the above attached diagrams are as follows:

[0014] Among them, 1. Large wrap angle paper passing roller; 11. Hollow roller body; 12. Roller shaft; 13. End cover; 131. Connecting channel; 132. Pneumatic connection; 2. Air outlet; 3. First sealing ring; 4. Second sealing ring; 5. Small wrap angle paper passing roller. Detailed Implementation

[0015] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0016] An air-floating stationary paper guide mechanism for rotary printing equipment includes a large-angle paper guide roller 1 with an wrap angle greater than or equal to 150°, which is fixedly mounted on the frame. The large-angle paper guide roller 1 has a working surface corresponding to the substrate, which refers to the arc segment of the roller surface in contact with the substrate in the prior art. The working surface is provided with a plurality of evenly distributed air outlets 2, which are arranged axially on the surface of the hollow roller body 11 in multiple rows. The air outlets 2 in adjacent rows are staggered to ensure more uniform support force on the substrate. The air outlets 2 are connected to an external air source and are only located in the working surface area to avoid excess airflow interfering with the paper path operation. The large-angle paper feed roller 1 includes a hollow roller body 11, a roller shaft 12, and an end cap 13. Both ends of the hollow roller body 11 are fixedly connected to the roller shaft 12 via the end cap 13. The end cap 13 is fixed to the roller shaft 12 by locking screws. One of the end caps 13 has a connecting channel 131 that communicates with both an air outlet 2 and an air source. Specifically, the hollow roller body 11 and the end cap 13 are connected by a first sealing ring 3, and the end cap 13 and the roller shaft 12 are connected by a second sealing ring 4, forming a sealed chamber. The air outlet 2 communicates with the sealed chamber, and the connecting channel connects the sealed chamber to the air source. During operation, compressed gas can be blown out from the air outlet 2, creating an air film gap between the substrate and the working surface of the large-angle paper feed roller 1. The compressed gas lifts the substrate, further creating an air film gap between the substrate and the large-angle paper feed roller 1. This gap prevents the inertia caused by the start and stop of the large-angle paper feed roller 1 from affecting the substrate. In addition, in order to ensure that the air outlet 2 corresponds to the substrate, the large wrap angle paper roller 1 needs to be fixedly set so that the working surface remains stationary in the working state, and the air film gap is stably formed.

[0017] To accommodate substrates of different thicknesses, the inlet side of the connecting channel 131 is equipped with a pneumatic connector, which is connected to an air source via a regulating valve.

[0018] The working principle of this utility model is described below with reference to the accompanying drawings: The movement of the printing substrate can rely on an active traction mechanism, which is existing technology and will not be described in detail here. When the printing substrate passes through the large-angle paper feed roller 1, compressed gas is blown out of the air outlet 2. The compressed gas lifts the printing substrate on the large-angle paper feed roller 1, so that an air film gap is formed between the printing substrate and the large-angle paper feed roller 1, thereby effectively reducing the contact between the printing substrate and the surface of the large-angle paper feed roller 1.

[0019] In the description of this invention, it should be understood that the terms "center," "length," "width," "thickness," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0020] In summary, the above description is only a preferred embodiment of the present utility model. All equivalent changes and modifications made within the scope of the patent application of the present utility model shall fall within the scope of the patent of the present utility model.

Claims

1. An air-floating stationary paper guiding mechanism for rotary printing equipment, comprising a large wrap angle paper guide roller (1) with a wrap angle greater than or equal to 150°, characterized in that: The large wrap-around paper feed roller (1) is fixedly mounted on the machine frame. The large wrap-around paper roller (1) has a working surface corresponding to the printing substrate, and the working surface is provided with a number of evenly distributed air outlets (2). The air outlet (2) is connected to an external air source; During operation, compressed gas can be blown out through the air outlet (2) to form an air film gap between the substrate and the working surface of the large wrap angle paper roller (1).

2. The air-floating stationary paper guiding mechanism for rotary printing equipment according to claim 1, characterized in that: The air outlets (2) are arranged axially on the surface of the hollow roller body (11) and are distributed in multiple rows, with the air outlets (2) in adjacent rows being staggered.

3. The air-floating stationary paper guiding mechanism for rotary printing equipment according to claim 2, characterized in that: The large wrap-around paper roller (1) includes a hollow roller body (11), a roller shaft (12), and an end cap (13). The two ends of the hollow roller body (11) are fixedly connected to the roller shaft (12) by end caps (13), and one of the end caps (13) has a connection channel (131) that is connected to the air outlet (2) and the air source respectively.

4. The air-floating stationary paper guiding mechanism for rotary printing equipment according to claim 3, characterized in that: The inlet side of the connection channel (131) is equipped with a pneumatic connector, which is connected to the air source through a regulating valve.

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