JPH0450288Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention relates to the structure of rolls, and more specifically to contact rolls, bonding press rolls, etc. attached to winders and feeders for webs such as paper and film. Regarding the structure of

(Prior Art) A contact roll is used in a winding machine for paper, film, etc. so that the rolled web can be wound up neatly without wrinkles. This contact roll is configured to change the flow direction of the continuously conveyed web and to press the surface of the web wound into a roll. However, at the pressing portion of the contact roll, air is also drawn in at the same time as the web is rolled in, and the roll web containing air has the disadvantage that its ends become uneven and wrinkles occur.

In order to solve this problem, a contact roll as described in, for example, Japanese Utility Model Application Publication No. 193346/1983 has been proposed. In order to prevent air from being entrained in the web and expel the entrained air, this roll has a roll body formed by forming an outer sheath of rubber, synthetic resin, etc. around the outer periphery of a pipe-shaped roll core. A striped member is wound around the outer periphery of the roll body, the direction of which is reversed at the center of the roll body, and which projects from the roll body at a certain height.

Such rolls were generally manufactured by the following method.

That is, after coating the outer periphery of the roll core with rubber to form an outer cover, this is first vulcanized. After vulcanization, predetermined spiral grooves are carved on the surface of the rubber layer forming the outer cover. Next, a separately vulcanized striped member is embedded in the groove of the roll body and bonded together, or an unvulcanized striped member is embedded in the spiral groove and vulcanized again. It was manufactured in one piece.

(Problems to be Solved by the Invention) However, each of the above conventional roll structures has the following problems.

That is, this type of contact roll is located at the introduction part of the winding and is configured to change the flow of the continuously conveyed web and to press the surface of the web wound into a roll with a constant force. ing. When pressing the roll web, force is applied to the shaft, causing the roll to flex and the nip width to become uneven. In order to make the nip width uniform, the outer circumferential surface of the roll may be processed to have an arc shape in cross section, that is, to form a crown. However, although a uniform nip width can be obtained with a crowned roll, the rotation speed differs between the center and both ends of the roll due to the difference in circumference. This causes problems such as wrinkles in the roll web and loss of shape.

In addition, the crown-processed rolls are
It is difficult to provide a striped member for preventing air entrainment and removing wrinkles as described in Japanese Patent No. 193346. This is because with a crowned roll, it is extremely difficult to process the grooves for providing the striped members and to polish the packed striped members.

(Means for solving the problem) This idea was made in view of the above,
In order to solve the conventional problems, make the nip width uniform, and prevent air from being drawn into the web wound into a roll, the following structure was adopted.

That is, two cover layers, an inner cover layer and an outer cover layer, made of a flexible material are provided on the outer periphery of the roll core, and the inner cover layer is made of a softer flexible material than the outer cover layer so that the outer diameter is at the center. Alternatively, the inner cover layer may be formed of a harder and more flexible material than the outer cover layer so that its outer diameter gradually increases from the center toward both ends; The outer cover layer is formed to have the same outer diameter over its entire length, and has a structure in which a spiral groove whose direction is reversed at the center of the roll body is carved on the outer peripheral surface.

(Example) Hereinafter, the structure of the roll according to this invention will be explained in detail.

FIG. 1 is a sectional view, and FIG. 2 is a partially enlarged sectional view. The roll body 1 includes a pipe-shaped roll core 3 having shafts 2 at both ends, an inner cover layer 4 formed on the outer peripheral surface of the roll core 3, and an outer cover layer 5 provided on the outer periphery of the inner cover layer 4. The outer cover layer 5 is provided with a spiral groove 6 whose direction is reversed at the center of the roll body.

The inner cover layer 4 and the outer cover layer 5 are, for example,
It is made of flexible materials such as rubber and plastic, and has different hardness. Inner cover layer 4 and roll core 3
In order to improve the adhesive strength with the roll core 3, the surface of the roll core 3 is treated by shot blasting or sandblasting, and after applying an adhesive to the surface, the inner cover layer 4 is formed. The inner cover layer 4 is formed in an arc shape, and its outer diameter gradually decreases from the center toward both ends. In this way, when the inner cover layer 4 is formed into an arcuate shape, it is preferable to use a softer and more flexible material than the outer cover layer 5.

The outer cover layer 5 is coated and bonded to the outer periphery of the inner cover layer 4 with sufficient strength, and its outer diameter is made equal from one end to the other end. Therefore, the outer cover layer 5 is formed to be gradually thicker from the center toward both ends. The outer cover layer 5 is made of a harder and more flexible material than the inner cover layer 4, and the amount of compression of the cover layer as a whole is smaller toward both ends than in the center.

Further, in the roll according to this invention, a spiral groove 6 whose direction is reversed at the center of the roll body 1 is carved on the outer peripheral surface of the outer cover layer 5. The cross-sectional shape of the groove 6 is an ellipse, and the opening is narrowed. That is, the width of the opening of the groove 6 is smaller than the maximum width inside. By closing the opening of the groove 6 in this way, compression becomes easier.

3 and 4 show cross-sectional shapes of grooves in other embodiments, and FIG. 3 shows a trapezoidal dovetail groove 6.
Fig. 4 shows a case where a substantially U-shaped groove 6b, which is a part of a circle cut out, is carved. In these embodiments as well, the diameter of the opening is smaller than the maximum diameter inside, and the opening is narrowed.

In the above embodiment, the outer periphery of the inner cover layer 4 is formed into an arc shape, but contrary to this, the inner cover layer 4 is formed into a drum shape with a constricted center, that is, the outer periphery of the inner cover layer 4 is formed into an arc shape. The diameter may be formed to gradually increase from the center toward both ends. In this case as well, the outer diameter of the outer cover layer 5 is formed to be the same from one end to the other, and a flexible material softer than the inner cover layer 4 is used. Therefore, the amount of compression of the cover layer in the roll as a whole is smaller toward both ends than in the center. Since the formation of the grooves in the outer cover layer 5 is the same as in the previous embodiment, the explanation thereof will be omitted.

(Effect of the invention) As explained above, the roll according to this invention has two cover layers and has a structure in which the amount of compression gradually decreases from the center toward both ends, so the outer diameter of the roll is The nip width is uniform even if it is the same from one end to the other, and a uniform rotational speed can be maintained as a whole roll.
Wrinkles do not occur in the roll web.

In addition, since the roll outer diameter is uniform, it is easy to create grooves, and the grooves prevent air from getting into the roll web and expel the trapped air, making it possible to completely remove air between the roll webs. can.

[Brief explanation of the drawing]

Fig. 1 is a front sectional view showing an outline of the roll according to this invention, Fig. 2 is a partially enlarged sectional view of Fig. 1, and Figs. 3 and 4 are parts showing other embodiments of the groove shape. It is an enlarged sectional view. 1 is a roll body, 2 is a shaft, 3 is a roll core, 4 is an inner cover layer, 5 is an outer cover layer, 6, 6a, 6
b is a groove.

Claims (1)

[Scope of utility model registration request] Two cover layers, an inner cover layer and an outer cover layer, made of a flexible material are provided on the outer periphery of the roll core, and the inner cover layer is made of a flexible material that is softer than the outer cover layer, and the outer diameter is from the center. Alternatively, the inner cover layer may be formed of a harder and more flexible material than the outer cover layer so that its outer diameter gradually increases from the center toward both ends. A structure of a roll characterized in that the layers are formed to have the same outer diameter over the entire length, and spiral grooves are carved on the outer circumferential surface of the roll body, the direction of which is reversed at the center of the roll body.