KR800000818B1 - Nip roller for web treatment - Google Patents

Abstract

A nip roll which comprises an inner substantially cylindrical member constructing a substantially rigid material, a cover member of a generally incompressible substantially resilient material positioned in said inner member, secured to outer surface portion thereof and reinforcing means positioned in said cover member having a tensile modulus of elasticity larger than modulus of the generally incompressible substantially resilient material. All of said reinforcing means sloped off substantially at the same acute angle with an associated auter surface portion of the inner member and in the same direction around the inner member such that upon positioning the roll in adjacent engaged rotational relation with a mating roll so as to creat a nip.

Description

Nip rolls for web processing

FIG. 1A is a cross sectional view of a nip roll coated according to the prior art which forms a nip with a conventional rigid roll.

FIG. 1B is a displacement chart of point A on the covering roll surface of FIG. 1A, and is a displacement diagram for point B on the inner core surface which is inward in the center direction than point A. FIG.

FIG. 1c is a velocity plot derived from road 1b.

Figure 2a is a cross-sectional view of a nip roll having a reinforcing coating material according to the invention in a nip with a conventional rigid roll.

FIG. 2b is a displacement chart of point A 'on the surface of the covering roll of FIG.

FIG. 2C is a velocity plot derived from FIG. 2B.

3 is a side view of a compression apparatus using the nip rolls of the present invention to compress web material.

4 is a cross-sectional view of a pair of oriented recovery wool illustrating another embodiment of the present invention.

5 is a cross-sectional view of the roll of the invention used for web stretching and / or cutting device, nipping with a conventional rigid roll and rotating in the opposite direction to the roll shown in FIG. 2a.

Figure 6 is an enlarged view of a part of the roll for explaining the manufacturing method of the roll of the present invention.

7 is a cross-sectional view of a roll manufactured according to the method illustrated in FIG.

FIELD OF THE INVENTION The present invention relates to rolls for compressing and stretching web materials, such as paper, nonwovens, etc., ie rolls for web processing.

In industrial use of paper, woven fabrics, nonwovens, etc., given in web form, it has been found to be beneficial to compress these materials to increase their density while softening tissue and increasing extensibility. For example, if you make a paper bag for packaging a large volume of product, you need to make it a coarse and extensible material to prevent the bag from tearing when you ship it. Compressing web-shaped paper cloth increases its strength and elasticity, as well as slightly softening tissue. It has also been found that even in webs such as woven or nonwoven fabrics, compression, can increase strength, tissue and stretch in the same way.

Conventional apparatuses have been developed to compress such webs using a dual roll compressor capable of forcing the web face in a size and orientation sufficient to compress these webs to conform to the commercial specification. Conventional double roll compressors used soft rolls coated with soft rubber and either steel rolls or cast iron rolls to compress the web material passing through the nip portion. As described below, in order to compress the web material within the web surface, it is necessary to asymmetrically displace the incompressible material (such as rubber) that forms part of the coating of the nip roll. This displacement of the material restores the rubber at the nip exit and reduces the net velocity of the deformable cladding surface in contact with the web material in the transverse direction of the nip, thus providing sufficient compression of the material in the transverse direction of the nip and web surface. The difference in speed and force will appear.

In the prior art, steel rolls and rubber coated rolls had to be rotated at different speeds to create asymmetric conditions. The steel rolls had to be rotated on the highway so that the rubber was pushed into the nip by the steel rolls at the nip inlet, and the rubber was restored at the nip outlet to compress the web material therebetween. In practice, the required speed difference was achieved by braking the speed of the rubber-covered rolls using a generator, which recovered this power and applied additional input to drive the steel rolls. However, there are some self-defects in such a device, the most important of which are as follows.

1) To allow power to be recirculated through the compressor, very large and expensive motors, generators and electrical controls are needed.

2) The compressor should be able to accommodate the excess rotational force that is recycled in this way.

3) Power loss due to conversion inefficiency.

This type of device is mainly known as an “MD compressor”, which means that the web moves through the nip in the machine direction (MD).

Among the known apparatus, there is a pressurized roller for papermaking which is provided with a waterproofing force to squeeze out excess moisture from a pile of paper using a sulfide rubber having a hole formed therein and air bubbles formed around the hole. Also known are calender rolls, which have inherent heat resistance and whose body and surface are suitable for calendering machines used in materials such as fibers or paper. The roll consists of a shaft holding the roll body in a compressed state between the flanges at both ends thereof, and a roll body in which a fiber material containing derubberized ramie fibers is superimposed. Also known is a super calender mechanism for paper, which consists of vertically stacked rolls and a frame device, which is arranged vertically by alternating a series of hard and soft rolls to contact each other by the frame device. It is supposed to rotate while being held in a state, and has a device for supplying a paper to be supercalendered to a roll stack, and a device for removing the paper after it has passed through the stack. A drive is provided for driving the lowest roll of the stack, and the outer portion of the soft roll is of polyaryl carbonate material. Still another is a roll coated with a special elastic body having an inner operating part and an outer non-operating part. The inner actuating section is perforated by a longitudinal helical channel to solve the compression difficulties caused by the elastomer and also to flow the cooling fluid for temperature control. The modulus of elasticity of the outer non-actuating portion is higher than the modulus of elasticity of the inner actuating portion so that the outer actuation of the outer surface of the roll can be sufficiently isolated from the inner actuation of the conduit. Also known are calendar rolls having a central core and discs suitable for the core which are compacted together to form a rigid filler, the discs having a biaxially oriented molecular structure. Made of a plate polymer having Other calender rolls are also known which consist of coated polymer rolls and which are capable of relative movement between the roll and the sheath under operating conditions but which are fixed in frictional engagement with a rigid mandrel under stationary conditions. However, there has been no suggestion so far of a web processing nip roll having a reinforcing elastic coating which is constructed such that the incompressible elastic material is uniquely asymmetrically deformed during the nipping rotation to achieve the desired web treatment as in the present invention. Moreover, no single roll has been proposed that can compress, stretch and shrink paper, woven and nonwoven materials without the need for complex external differential drives.

Hereinafter, the gist of the present invention will be described.

According to the present invention, a coating material made of an incompressible elastic material is disposed around an inner cylindrical member made of a rigid material and fixed to the surface of the cylindrical member, and also engaged with the second roll to rotate and perform a nipping action. Nip rolls for web processing are provided. Reinforcement means are included in the cladding, which has a greater elastic modulus than the incompressible elastic material, and each reinforcement is inclined at an acute angle with respect to the outer surface of the inner member, thus engaging and rotating the roll adjacent to the fitting roll. If arranged so that a nip is formed between these rolls, this oblique orientation and high modulus of elasticity of the reinforcing means are combined to cause relative displacement and restoration of the incompressible material at the nip inlet and outlet, thereby at least the surface of the incompressible material at the nip inlet side. Since the velocity is different from at least the surface velocity of the incompressible material at the nip outlet side, a pure force is generated in the transverse direction of the nip, thereby making it possible to control the treatment of the web or the like in a preferred manner.

In the preferred embodiment, the coating of the nip rolls is composed of rubber and fiber composites and elastics, or woven polyester textile fibers and elastics forming a reinforcement core, which is rigid outside steel or cast iron compared to the nip rolls of the present invention. When rotating and nipping in conjunction with the roll, the displacement of the elastic material, which is the covering material of the roll of the invention, is sufficiently asymmetrical so that the force acting on the web within the web surface by the roll member when the feeder or other web passes through the nip Compresses the material, thus making the web softer and considerably more extensible than the uncompressed material. Elastic materials consist of either synthetic or natural rubber.

Thus, as can be seen in the following description, the rolls of the present invention can generate a pure force in the web surface without the need for complex external drives or other devices as in the prior art rolls. Furthermore, the reinforcing material of the woven polyester textile fiber is partially embedded in the rubber coating, and as the fiber reinforcing portion approaches the nip working area, the reinforcing portions approach almost parallel coincidence with the web material in the nip. By rotationally driving the rigid roll in the direction, the net force acting on the web material will have a compressive force within the web surface.

In an adopted embodiment, the fiber / rubber composite or fiber reinforcement layer of woven polyester forms a coating with a layer of synthetic rubber material interposed therebetween, wherein the rubber material is stiffened before the rubber material is cured by a suitable binder solution. It was found that sticking the layers together results in an exemplary result. In addition, in the adopted embodiment of the roll of the present invention, there is an unreinforced rubber layer on the outside of the roll to form a continuous outer surface of the roll, and the coating material is formed of a separate layer from the rubber material, thereby forming small discrete gaps. In addition, at least two layers of unreinforced rubber material are placed around the rigid cylindrical member and between the member and the original covering, with the hardness of the inner rubber layers becoming lower and lower from the inner member to the outer surface. It has been found to be more desirable when the hardness of the constituent material of the roll is reduced from the inner core to the outermost cladding.

For this purpose, the hardness measurement parameter of the rubber measured on the A scale of the Shore Scleroscope is called the "hardness ratio" of the elastic material. In the adopted embodiment of the present invention, the specific hardness ratio of the roll element of the present invention has been studied to be optimal, and it should be noted that such a hardness ratio is relative and is not necessary for the accurate implementation of the present invention, but only in the adopted embodiment. Is that only necessary. Furthermore, other suitable rubber hardness parameters, i.e. conventional rubber hardness parameters, having values close to the hardness ratios described herein can also be used as indicators for practicing the present invention.

In Zippo, this apparatus was squeezed by the apparatus of the present invention using a roll with reinforcing coating material, and the moisture content was calculated according to the following equation, and it was found that the moisture content was 30-40%.

However, in the case of paper with a relatively high moisture content such as 50-60%, the frictional force is significantly reduced, and the asymmetric structure and displacement of the elastomeric coating material during the rotation of the rolls prevents the web material from compressing properly. This can cause you to be dragged or pied. By arranging the two rolls according to the invention in an interlocking nipping relationship, the sliding force between the roll and the web must be eliminated by applying the same compressive force to both sides of the web material. As a result, the form of force on both sides of the web becomes fully symmetrical. The apparatus of the present invention adequately compresses relatively low friction web materials without attracting or crushing the paper surface despite providing less compressive force to the paper material as compared to the embodiment employed. According to this device, the roll of the present invention having a reinforced cladding material rotates in a nipping during rotational driving with the same type of roll so that the warp reinforcing member in the elastomeric cladding is oriented parallel to the web material passing through the nip of the roll.

An additional feature of the rolls of the present invention is that the rolls can stretch the web material when rotating to form a nipping with a rigid roll that is rotationally driven opposite to the roll direction of the adopted embodiment. From the following detailed description, it can be seen that the rotation is achieved in such a way that the warp reinforcing member embedded in the elastomeric covering of the roll of the present invention rotates to approach the web material in an orientation substantially perpendicular to the web surface. Such a device displaces the elastic material toward the nip inlet and restores the displaced elastic material at the nip outlet, the restoring force occurring in the direction of movement of the web, causing the web to increase with increasing velocity of the elastic material from the inlet to the outlet of the nip. It is elongated. Web materials, such as paper with low tensile strength, cannot tolerate this stretching force, so that the paper tears as the web progresses in the longitudinal direction of the roll, thereby easily cutting the paper. Thus, the roll of the present invention may include a useful part of the paper cutter mechanism.

According to the present invention, a method of generating a force on a web surface for treating a web material such as paper is proposed, which is performed as follows. In other words, a nip is formed between the two members, at least one of which is a roll mounted to rotate in a cylindrical shape, consisting of an inner roll core and an outer sheath mainly made of an incompressible elastic material. A method of passing a web material through a nip. In addition, the method also allows the nipping force on the roll to displace a portion of the elastic material asymmetrically around the nip so that the material displaced in the first direction on one side of the nip is restored to its original position toward the inner roll core on the opposite side of the nip. Determining the structure of the outer sheath of the roll so that the nipping force is applied asymmetrically onto the web material as the web material is moved through the nip. In the adopted embodiment, the method consists of at least two rolls, one of which is a rigid roll, so that the two rolls are arranged adjacent to each other so that they are rotated and nipped. Preferably the present invention embeds the reinforcing member in the incompressible material, wherein the elastic modulus of the reinforcing member is made larger than the elastic modulus of the incompressible material of the outer cladding and the rotation of the rolls is such that the incompressible material is displaced toward the outlet side of the nip. And to determine its structure. By continuously rotating the rolls and the web nibbed between these rolls together, as the web gradually exits the nip, the displaced incompressible material is restored to its original position relative to the inner roll core to The surface velocity is made smaller than the velocity of the corresponding surface portion at the nip inlet side, whereby an asymmetrical force is applied to this web material within the web surface and also in the cross direction of the nip.

The present invention also relates to a new and useful method of making a nip roll as described above, which method creates a cylindrical member from a rigid material and forms a continuous strip of incompressible elastic material, the strip having an arc shape and an elastic strip and a cylindrical roll. It is attached along the length of the roll so that it extends at an acute angle to a plane in contact with the rigid cylindrical roll passing along the contact line therebetween, wherein the arc shape has an angle between the elastic material and the contact surface at the free end of the elastic strip. It is larger than the corresponding angle at, and the reinforcing fiber portion is laminated thinly on the elastic region so that the fibers exhibit an arc shape in the elastic region, and the thin elastic layers are alternately stacked in the same form as the first elastic region. Fiber-reinforced elastomeric sheath covering the entire circumferential surface of the cylindrical roll, the entire reinforcing elastomer The rolls coated with the carbon steel are placed in an air impermeable container, and the coated rolls are cured to at least partially softened elastic material, and then cured. And a method of forming a uniform continuous circular cladding. By attaching elastic strips to the preceding reinforcing fiber strips, a side rolling apparatus is used in which each elastic strip is rolled and simultaneously exerted downward pressure so that the contact surface between the elastic strip and the reinforcing fiber strip is in full contact. desirable.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, FIG. 1A shows a cross-sectional view of a conventional roll 10 covered with non-reinforced rubber, nipping together with a conventional steel furnace 12. The rubber cladding 14 is elastic and incompressible so that it is asymmetrically displaced in the nip portion as shown and lumps bulge at both the nip outlet and the nip inlet. The part indicated by the dashed line in FIG. 1 a represents the displacement of the rubber material. When the rolls rotate in the direction shown, for point A on the rubber surface, the tangential displacement “D” with respect to point B on the surface of the core 16 inwardly centered at this point is a function of time “T”. As shown in FIG. 1b.

From the displacement plot of FIG. 1b, the tangential velocity "V" over time "T" is easily derived according to the following equation.

는 시간 “T”에 대한 거리 “D”의 1차 도함수이다.only

Is the first derivative of the distance "D" over time "T".

A velocity plot for the roll 10 of the prior art is shown in FIG. 1C. As can be seen from this diagram, the velocity at point a has a value of V _AO less than the velocity V _S of the steel roller 12. As point A approaches the hump of the nip, this speed decreases momentarily due to rubber displacement and then accelerates to the same speed as the steel roll as the nipping takes place. Because of the frictional force, the speed of the rubber surface remains the same as that of the steel rolls throughout the nip. After passing through the nip, the speed of point A again decreases from the normal speed V _A and then increases back to the original speed V _AO as point A continues to rotate and leaves the nip. As such, the velocity of the rubber surface at the nip inlet and nip outlet is approximately equal to the surface velocity of the steel roll 12, and the web material is neither compressed nor stretched through the roll. Therefore, to compress the web material with the apparatus of FIG. 1a, it is necessary to use a complex apparatus that causes the asymmetric nip by varying the speed of each roll.

In figure 2a a roll 20 according to the invention is shown. The inner core member 22 is in the form of a cylindrical steel roll, and the rubber covering member 24 having the reinforcing cords 26 arranged at an acute angle with respect to the intersection with the outer surface of the inner core member 22 is provided with the inner core member ( It is located outside of 22). The steel roll 12, which is adapted to rotate with the roll 20 of the present invention, is driven from the outside by a conventional drive (not shown).

The modulus of elasticity of the reinforcing cord 26 is defined as follows.

The value of the elastic modulus (E) of this reinforcing cord is larger than that of the basic rubber material used as the cladding. Such reinforcing materials are made of woven or nonwoven fabrics such as polyester, nylon, cotton, and the like, and are preferably oriented so as to extend in the direction of greatest elastic modulus, ie, in the general direction of movement of the web material. Also preferred is reinforcement means such as fiber / rubber composites oriented to reinforce the coating. However, in the case of using the woven reinforcing material, it is preferable to use a uniform mesh woven polyester textile fiber so that the weft yarn is disposed in the machine direction. In this case, the inclination extends in the longitudinal direction of the roll.

Referring back to FIG. 2A, the reinforcement cord 26 does not stretch when the roll 20 and the roll 12 rotate in the direction shown, while also preventing rubber from displacing towards the inlet side of the nip, while the nip It can be seen that there is almost no resistance to bending by the nipping force on the outlet side. Thus, the point A 'on the cladding 24 is displaced as indicated by the dotted line in FIG. 2A, where the tangent of the point A' with respect to the point B 'on the inner steel core 22 inwardly in the center direction than the point A'. Directional displacement is shown in 2b. Since the displacement of the rubber appears all in the same direction as shown in the conversion portion 28 of FIG. 2A, the stress which displaces the rubber in this way increases to a substantial level.

As the rotation continues, the force caused by this stress becomes greater than the frictional force between the roll surfaces, and once the cladding 24 is out of the influence of the nip, the displaced rubber portion is shown in the velocity diagram in FIG. As will be restored to the original position with respect to the inner core. The point A 'on the outer surface of the roll covering 24 will thus have a velocity form as shown in FIG. 2C with respect to the point B' on the outer surface of the inner core 22. The speed V ' _A ' at point A 'will initially be V' _A ' _O and will accelerate to the same level as the steel roller speed V' _S as the nipping takes place. Since the rubber cord 26 limits the displacement of the rubber material, in particular because the reinforcement cord elastic modulus is particularly oriented with respect to the natural flow tendency of the incompressible rubber material, the velocity at point A 'is not increased before the nipping takes place. It does not slow down.

During the nipping, the speed of point A 'and the speed of the corresponding point on the steel roller are the same, and are constant until the rotational position reaches the point where the restoring force of the rubber overcomes the friction between the roll surfaces. At this point, due to the restoring action of the rubber material to be restored to its original position on the roll, the speed V ′ _A ′ decreases rapidly to the minimum value V ′ _R , and then beyond the effect of the nip to have the original value V ′ _A ′ _O. do.

From the velocity diagram at point A ', it can be seen that the speed when the rubber surface enters the nip is significantly greater than the speed when this rubber surface exits the nip. As the web 18 of paper (or woven or nonwoven) passes through the nip, the speed of this web will be the same as the speed of the rubber, so the web, like rubber, also leaves the nip at a smaller rate than when entering the nip. do. This speed difference is a measure of web shrinkage. The improvement in compression is due in particular to the asymmetric displacement of the rubber due to the high modulus of elasticity of the reinforcement cord and the reinforcement cord being oriented in a special oblique orientation with respect to the direction of rotation of the roll 20.

3 shows the compression roll of the present invention, which is an operating part of the compression device 41. The roll 20 of FIG. 2a is rotatably mounted to the bracket 30 (only one side in the drawing), which is supported by the pivot pin 34 and the lever 36 to support the vertical support 32. It is supported pivotally in the phase. A rigid roll 12 made of steel or cast iron is supported by a shaft 38 on a bracket 40 mounted on a vertical frame 32. The steel roll is rotationally driven in the direction shown by an external rotation drive (not shown). When the roll 20 is disposed in a face-to-face bond with the steel roll 12, a nip is formed between the roll 20 and the rigid roll 12. The nipping force is proportional to the actual compression rate (%) of the rubber cladding, which is also controlled by the lever 36 which converts the linear force of the piston rod 43 of the air cylinder 42 into a rotation moment (force x distance). It is proportional to the downward force transmitted on the roll 20. Thus, the nip plain force, measured as the weight per linear distance of the roll (pounds per linear inch, pli), depends on the nip trunk% (or% compressibility of the rubber cladding), and the nip interference rate is also the linear motion of the actuator piston rod 43. And the force generated by the actuator 42. For example, in the case of the compression apparatus shown in FIG. 3, the diameter of the inner core 22 of the roll 20 may be reduced to sufficiently compress the zips so that they can be stretched (or stretched) within the scope of the commercial specification. At 20 inches, about 0.4-0.6 horsepower per unit inch length of the roll (ie per unit inch width of the machine) is provided to the device shown to produce a load of about 250-350p1i and 8-10% nip interference. .

In the operation of the FIG. 3 apparatus, when the uncompressed zippo 18 passes between the roll 20 and the steel roll 12 of the present invention as shown in FIG. 3, the reinforcing cord 26 is As shown in FIGS. 2 and 3, the displacement of the rubber is asymmetrical as described above and also at the nip outlet side of the roll 20 because it is constructed and oriented to approach the steel roll in substantially parallel relation to the web. Limited. Since the restoring force of the reinforcing roll covering rubber makes the speed at the nip outlet side smaller than the speed at the inlet side, the web passing therebetween is compressed.

Although the rolls modified according to the invention are particularly useful for web compression as described above, it has been found that the apparatus is particularly suitable for zip compression with a water content of 30-40%. For example, a zippo with a relatively high moisture content, such as 50-60%, was found to be damaged at least one side when processed with the apparatus of FIG. Due to the adhesion between the paper and the steel roll, the paper can no longer be compressed the moment the rubber cladding is restored. Thus, the increased frictional force due to the high moisture content of the zippo causes the roll to exert shear forces on the web material along the plane through which the shear forces tend to shear the web around it. If the applied force is greater than the shear strength of the paper, the paper will boil or tear. Steel rolls with special surfaces, such as those known as “brame” surfaces, are sometimes used in the form of two roll compressors that compress webs with high moisture content. One drawback is that, for example, the roll is embossed, which is embossed on the surface of the fabric, which is undesirable for various purposes. These brain surfaces are prone to uneven operation and are difficult to recreate good operating conditions.

4 shows a twin reconstruction “MD” compression device using two rolls according to the present invention, which is particularly suitable for zippo compression with a high moisture content on the order of 50-60%. The roll 20 in FIG. 4 is meshed so that the same roll 21 may rotate. One of these rolls is driven from the outside by a drive (not shown). Since the device generates symmetrical forces on both sides of the paper 18, the paper does not slip or tear even when the paper has a higher moisture content than usual. The reinforcing cords 26 are oriented as before and the rolls 20 and 21 have the same speed profile and rubber recovery properties as the rolls 20 described above. However, the two rolls 20, 21 are identical to each other, and the friction is minimized because the two rolls nip and release the web simultaneously and symmetrically with respect to the web.

The FIG. 4 apparatus is advantageous in that it can compress high moisture content webs, but the compressibility by this apparatus is not the same as that in the reinforcement rubber coated rolls that are nipping together with the steel rolls described above. For example, in the device described above, the steel roll 12 has a larger coefficient of friction than the roller roll of the present invention, so that the steel roll 12 is held for a longer time before falling off from the rubber-coated roll 20. The roller 20 tends to frictionally engage the roll 20, and the restoring force of the rubber material becomes greater. In the case of the dual restoration compression apparatus of FIG. 4, the rubber material of the reinforcing coating material 24 will be less restored than in the apparatus of FIG. 2A and the compression will be smaller. Despite these drawbacks, the ability to compress high moisture content blisters without tearing is recognized as a significant advance in the art.

It was found that, as shown in FIG. 5, when the reinforcing cord is rotated in the opposite direction such that the reinforcing cord is approached perpendicularly to the web, the web passing therethrough is stretched within the web surface. This result is due to the special displacement of the rubber material due to the relative orientation of the basic incompressible elastic material which is reinforced as described above in FIGS. 2a and 4 and which rotates in the opposite direction as described above. .

5, the reinforcement material 26 is shown with a roll 20 as described above having a covering material 24 embedded therein. The inner core material 22 has a coating material 24 made of an incompressible elastic rubber material. have. Reinforcement material 26 of woven polyester having a higher tensile modulus than rubber is embedded in the rubber cladding and, as shown, is also oriented as described above. The reinforcing material of this embodiment can also be made of other materials such as cotton, nylon, fiberglass, rubber, and the like. It is most important to incline the reinforcing material 26 at an acute angle with respect to the tangent tangent of the inner core 44. It is also very important to select a reinforcing material having a tensile modulus more than the basic rubber of the cladding 47.

With further reference to FIG. 5, the roll 20 is nipped to the rigid roll 12 as described above, but the direction of rotation relative to the reinforcing material 26 is as shown. As can be seen from the figure, the displacement of the rubber cladding 24 is made in the same direction as in the previous embodiment, but the web driven to enter the nip enters the nip surface on the side where the rubber is displaced. The rubber material is not displaced to the nip outlet side because of the resistance by the reinforcing material 26 in the outlet direction. On the other hand, since this reinforcing material shows relatively little resistance to bending, this reinforcing material shows little resistance to displacement of the rubber toward the nip inlet side. Continued rotation of the roll 20 and roll 12 as shown in FIG. 5 results in the forward restoring force appearing as the displaced material leaves the nip and returns to its original position relative to the inner core. As such, the velocity at any point on the surface of the reinforcing cladding 24 has a value greater than the velocity at the nip inlet side at the nip outlet side. This distribution of forces stretches the stretchable web material, such as woven or nonwoven, through the rolls 20 and 12. In the case of a zippo, a net tension greater than the tensile strength of the paper will shear the paper in the form of a uniform strip. The width of this strip will vary depending on a combination of factors including the diameter of the inner core, the diameter of the reinforcing rubber cladding, the relative difference between the elastic modulus of the reinforcing material and the elastic modulus of the rubber material.

Referring now to FIG. 6, a new method of manufacturing the improved compression roll of the present invention is shown. This roll is preferably made of a cylindrical steel inner core 44 as shown. Although a roll having a covering of an incompressible material having a reinforcing material oriented as illustrated in the preceding figures has already been described above, in practice, the ability to achieve the structure of the roll or to perform the above-described functions is provided. It has been found that the special features required to enhance should be included in the improved roll manufacturing according to the invention. As an example to more clearly illustrate the manufacturing method of the roll of the present invention and the relative size of each component, it is important that the steel inner roll core shown in FIG. 6 has a diameter of about 20 inches.

In FIG. 6, sufficient rubber plates are layered and superimposed on the surface of the steel inner core 44, thereby forming a covering 47 surrounding the inner core 44. As shown in FIG. Prior to fixing the rubber plate 46 to the steel inner core 44 in an overlapping relationship with each other, it is advantageous to reduce the surface strength from the surface of the inner core 40 to the outer surface of the covering 47. Therefore, initially, a non-reinforced, non-hardened rubber plate 58 having a degree of 90 D Durometer by the Shore A hardness gauge is fixed to the core 44 with a suitable bonding agent. . A second unreinforced uncured rubber plate 60 having a Shore A hardness of 70 durometer is then attached to the first rubber plate with a suitable binder. After this step is completed, the primary rubber cladding 47 is formed.

The rubber plate 46 is about 1/16 inch thick and has an arched structure as shown, making the radial thickness of the cladding 47 about 2 inches. As a result, the angle between these rubber plates and the tangent planes of the inner core material preferably decreases slightly toward the outer surface of the coating material. Since the thickness of the effective ply measured in the circumferential direction increases from the inner core member 44 toward the outer surface, the length of the circumference gradually increases. The actual shape of the arched rubber plate 46 required to achieve the structure shown is a spiral, but in the part shown is almost an arc. Preferably, the rubber plate 46 made of natural rubber having a Shore A degree of 50 durometer is attached to the inner core member 44 while being superimposed with each other by a suitable binder or binder such as resorcinol and the compound thereof. It also sticks to each other. In order to properly apply the initial rubber layer, a contour bar 48 as shown is placed on the inner core 44, wherein the working surface 51 of the contour bar 48 is shaped like this. It is approximately equal to the curved portion of the rubber plate 46 necessary to form a suitable roll covering 47. This rod 48 is completely removed before the roll covering is completed.

Each rubber plate 46 is sufficiently coated with a bonding agent or an adhesive and arranged to overlap the next rubber plate 46 along the longitudinal direction of the inner core material. When the arrangement of each rubber plate is completed, a downward force is applied to the rubber plate 46 while the contour roller 52 is moved in the longitudinal direction of the rubber plate to bond the surfaces together. At this time, a suitable reinforcing cord 49 made of polyester textile fibers between each rubber plate 46 is bonded to the surface of the rubber plate 46. The reinforcing cord 49 has a greater elastic modulus and adhesion than the rubber material, and is preferably constructed of about 800 denier polyester woven yarn. The rubber sheet 46 is preferably made of uncured rubber so that it can be cured when the roll covering is completed. After the rubber plate 46 is completely attached, a sheet of 1/4 inch unreinforced and non-hardened rubber plate is bonded to the outer surface. This rubber layer, with a Shore A hardness of 50 durometers, eliminates some nip discontinuity on the surface of the cladding, which is caused by the overlapping multiple layers of rubber plate 46.

It can be seen from the figure that, due to the special geometry of the assembled members as shown, a triangular inner space 54 is formed at the portion where the outer surface of the inner core material and the inner end of the rubber plate abut. When the roll covering is completed, the roll is sealed in an air impermeable material such as a plastic bag. At this time, the inside of the bag is vacuumed to remove air from the space 54. When the entire roll is treated in a pressure cooker by a suitable curing process such as a sulfiding process and at the same time maintaining a vacuum in the bag, a part of the rubber plate 46 and some rubber material of the inner layers 58 and 60 are adjacent to the space 54. As it flows in, the coating will be nearly uniform and have a concentric cross-sectional structure as shown in FIG. However, although the rubber parts have become generally uniform and homogeneous, each part still retains their individual properties such as different rubber hardness ratios. In addition, sulfiding the rubber sheet stabilizes the rubber material to be used and improves its properties.

The diameter of the inner core 44 is determined in each case. However, in the adopted embodiment, it was found that when the diameter of the inner core member 44 was 20 inches and the thickness of the roll covering member 47 was about 2 inches, exceptional results were obtained in the web processing. When such an inner core is used, when the angle "α" between the tangent plane 64 of the reinforcing cord 49 and the tangent plane 66 of the inner core at each intersection point is about 20 ° as shown in FIG. It has been found that the rubber sheet 46 and the reinforcing cord 49 can be used in the most optimal state. The curvature of the reinforcement cord 49 is also defined by the angle “β” between the tangent planes at the point where the reinforcement code 49 meets the outer surface of the roll, ie the two tangent planes 68, 70 in FIG. 7. It is desirable that it be determined so that the angle "β" can be maintained at about 16 degrees. By adopting the size and curvature of the rubber plate 46 and the reinforcing cord 49 as described above, a restoring force, a speed form, a form of force, etc. as desired are obtained.

Claims (1)

An inner cylindrical member made of a rigid material, a coating material made of an incompressible elastic material located around the inner member and secured to an outer surface of the inner member, the elastic material having an elastic tensile modulus arranged therein and having an elastic tensile modulus A nip roll consisting of reinforcing means having a value greater than the tensile modulus; wherein the reinforcing means are all inclined at the same acute angle with respect to the associated outer surface of the inner member and in parallel around the inner member, Is placed in its occlusal rotation and adjacent fitting rotation so that a nip is formed therebetween, due to the oblique orientation of the reinforcing means and its large modulus of elasticity, the velocity of at least the surface of the incompressible material at the nip inlet side Velocity of at least the surface of this incompressible material at the nip outlet side It is made different, whereby the web treatment nip roll (nip roll) according to claim created a force required for the web process to be controlled by.

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