Twisted cord manufacturing equipment and recycled pellet manufacturing equipment

Abstract

To provide: a reclaimed pellet manufacturing device that is equipped with a rotary compression part configured to apply twisting and compression to a loss film, and that does not cause quality deterioration problems even if rotational speed of the rotary compression part is increased to improve productivity; and a manufacturing device for twisted strings formed in a preliminary stage of a reclaimed pellet production process.SOLUTION: A compression part includes: a drive-side compression roller 38b; a pressure-side compression roller 38a that is movable toward and away from the drive-side compression roller 38b and sandwiches a loss film in cooperation with the drive-side compression roller 38b; a compression force adjustment mechanism that presses and urges the pressure-side compression roller 38a toward the drive-side compression roller 38b; and one or more weights 86 attached to the pressure-side compression roller 38a. A point of action S of a centrifugal force fc acting on the weight 86 or the point of action S of a resultant force fc of respective centrifugal forces fc1, fc2... acting on the plurality of weights 86 is located closer to the drive-side compression roller 38b than a rotation center O of the rotary compression part.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a twisted cord manufacturing device and a recycled pellet manufacturing device that use, as raw materials, edge portions that are scraps from the cut ends of double-layered film manufactured by inflation molding, and other product losses that occur during the manufacturing process (for example, double-layered film with poor thickness or that is torn during the process, or raw material loss when changing products). [Background technology]

[0002] It has been widely practiced to process the large amount of waste film (long, width-sized edges and product waste) generated during the manufacturing process of resin films and other materials into recycled pellets.

[0003] One example of an apparatus for producing such recycled pellets is known from Patent Document 1. A conventional recycled pellet production apparatus produces recycled pellets by cutting a twisted string formed by twisting a loss film, and is roughly composed of a loss film supply section, a heating section, an intermediate feed section, a rotary compression section, and a cutting section.

[0004] The loss film supply section overlaps and folds one or more loss films to make them wide enough to pass through the next heating section, and then supplies them to the heating section.

[0005] The heating section heats and softens the loss film supplied from the loss film supply section, and the loss film that passes through the heating section is sent to the intermediate feed section.

[0006] The intermediate feed section has a pair of upper and lower intermediate rollers, and the portion sandwiched between the intermediate rollers becomes the "twist starting point" of the loss film.

[0007] The loss film that has passed through the intermediate feed section is sent to the rotary compression section, which is equipped with a pair of compression rollers with uneven outer surfaces and a take-up roller connected to the pair of compression rollers. The rotary compression section rotates around the loss film while clamping the loss film between the compression rollers.

[0008] Here, the pair of compression rollers includes a drive side compression roller and a pressure side compression roller that can be displaced in a direction toward or away from the drive side compression roller, and the pressure side compression roller is pressed toward the drive side compression roller by a compression force adjustment mechanism attached to the pressure side compression roller.

[0009] The rotation of the rotary compression section imparts a "twist" to the loss film starting from the intermediate feed section, and the strong pressing force of the compression rollers point-presses the twisted loss film to form a crimped twisted cord with concave indentations. The crimped twisted cord with concave indentations is strongly pressed to form deep concave indentations, and is sent out as a flat twisted cord. The take-up rollers rotate in the sending-out direction while sandwiching the crimped twisted cord with the flat concave indentations, and send it to the cutting section.

[0010] The cutting section has a circular saw-shaped cutter, which rotates to cut the crimped twisted cord with concave impressions sent from the rotary compression section into short pieces at predetermined intervals, forming flat recycled pellets with concave impressions on both sides. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Patent No. 7004373 Summary of the Invention [Problem to be solved by the invention]

[0012] Users of conventional recycled pellet manufacturing equipment had been requesting the following: (1) to increase the production volume of recycled pellets, (2) to increase the density of recycled pellets more than ever before, and (3) to use loss films that are difficult to twist, such as hard or thick loss films, as raw materials.

[0013] In order to increase the production volume of recycled pellets, it is possible to increase the supply speed (conveying speed) of the raw material waste film, but increasing the supply speed of the waste film reduces the "number of twists" per unit length of the twisted string. Since a decrease in the number of twists leads to a decrease in the density (deterioration in quality) of the recycled pellets, it is necessary to increase the number of "twists" to compensate for this.

[0014] In addition, in order to increase the density of the recycled pellets, the number of twists per unit length of the twisted string can be increased. Also, when using loss film, which is difficult to twist, as the raw material, it is thought that the problem can be solved by giving it more twists.

[0015] In this way, it was thought that the above requests from users could be resolved by adding more "twist" to the loss film, in other words, by "increasing the rotational speed of the rotary compression section." However, there was a concern that increasing the rotational speed of the rotary compression section would reduce the pressing force of the compression roller, as described below, and make it impossible to obtain recycled pellets of satisfactory quality.

[0016] That is, since the rotary compression section is a rotor that rotates around the loss film as the center of rotation as described above, centrifugal force due to the rotational motion acts on the rotary compression section.

[0017] Naturally, centrifugal force also acts on the pressure-side compression roller provided inside the rotary compression section, and the direction of this force is opposite to the direction in which the compression force adjustment mechanism presses and urges the pressure-side compression roller toward the drive-side compression roller. In other words, the pressing force that the compression roller exerts on the loss film during the rotational movement of the rotary compression section (pressing force of the compression roller) is the value obtained by subtracting the "centrifugal force acting on the compression roller due to the rotation of the rotary compression section" from the "pressing force by the compression force adjustment mechanism."

[0018] Here, the centrifugal force increases as the rotation speed increases (when the mass force of the rotating body is m, the distance from the center of rotation to the rotating body is r, and the rotation speed is v, the centrifugal force is mv 2(The formula is / r.) This means that the higher the rotation speed of the rotary compression section, the lower the pressure of the compression roller. If the pressure of the compression roller decreases, the adhesion between the waste films decreases, and the resulting recycled pellets will be of low quality with low density.

[0019] The present invention has been made to solve these conflicting problems, and aims to provide a recycled pellet manufacturing device equipped with a rotary compression section that applies twist and compression to a loss film, in which the problem of deterioration in the quality of the recycled pellets does not occur even when the rotation speed of the rotary compression section is increased, and a manufacturing device for twisted strings formed in the preliminary stage of the recycled pellets. [Means for solving the problem]

[0020] The recycled pellet manufacturing apparatus 10 of the present invention is equipped with a loss film supply section 12 that clamps and sends out one or more loss films R1 together, which serve as the starting point K for twisting the loss films R1, a rotary compression section 14 that twists the loss film R1 sent from the loss film supply section 12 and point-presses it to impart a concave impression Y to form a crimped twisted cord R3 with a concave impression, and a cutting section 16 that cuts the crimped twisted cord R3 with a concave impression sent out from the rotary compression section 14 to a predetermined length. The rotary compression section 14 includes a rotary section 20 that rotates around the loss film R1 being conveyed as a rotation axis, and a compression section 22 that is provided within the rotary section 20. The compression section 22 includes a drive-side compression roller 38b, a pressure-side compression roller 38a that is displaceable toward or away from the drive-side compression roller 38b and cooperates with the drive-side compression roller 38b to clamp the loss film R1, a compression force adjustment mechanism 76 that presses the pressure-side compression roller 38a toward the drive-side compression roller 38b, and one or more weights 86 attached to the pressure-side compression roller 38a. The point of application S of the centrifugal force fc acting on the weight 86 or the point of application S of the resultant force fc of the centrifugal forces fc1, fc2, ... acting on the multiple weights 86 is located on the drive side compression roller 38b side relative to the center of rotation O of the rotary compression section 14.

[0021] As shown in Figures 3 and 4, the present invention works as follows. When the rotary compression unit 14 rotates, the centrifugal force fc of the weight 86 acts on the pressure-side compression roller 38a. The centrifugal force fc of the weight 86 acts in the opposite direction to the centrifugal force Fc of the pressure-side compression roller 38a. Therefore, the centrifugal force Fc of the pressure-side compression roller 38a is reduced by the centrifugal force fc of the weight 86 acting in the opposite direction.

[0022] Furthermore, when the magnitude of the centrifugal force fc acting on the weight 86 is set to be equal to or greater than the centrifugal force Fc acting on the pressure side compression roller 38a, the centrifugal force acting on the compression roller due to the rotation of the rotary compression section is offset by the centrifugal force fc acting on the weight 86, so that even if the rotation speed of the rotary compression section 14 is increased, there is no problem of deterioration in the quality of the recycled pellets P.

[0023] In particular, when the magnitude of the centrifugal force fc acting on the weight 86 is set to be greater than the centrifugal force Fc acting on the pressure side compression roller 38a, the pressing force of the compression rollers 38a and 38b increases the higher the rotational speed of the rotary compression section 14 (the faster the rotary compression section 14 is rotated), so that recycled pellets P having a higher density than before can be obtained.

[0024] The present invention further includes the following configuration: The point of application S of the centrifugal force fc acting on the weight 86 or the point of application S of the resultant force fc of each of the centrifugal forces fc1, fc2, ... acting on the multiple weights 86 is located on a straight line L passing through the center of gravity G of the pressure-side compression roller 38a and the center of rotation O of the rotary compression unit 14.

[0025] In this case, the centrifugal force fc of the weight 86 and the centrifugal force Fc of the pressure side compression roller 38a act on the same straight line and in opposite directions, so that the forces acting on the rotary compression section 14 during rotational motion are balanced, allowing the rotary compression section 14 to rotate stably.

[0026] It is also possible to remove the cutting section 16 from the recycled pellet manufacturing apparatus 10 and use the waste film supply section 12 and the rotary compression section 14 as the twisted cord manufacturing apparatus 100. Effect of the Invention

[0027] According to the present invention, when the rotary compression unit is rotated, the centrifugal force of the pressure-side compression roller is offset by the centrifugal force of the weight. Therefore, even if the rotation speed of the rotary compression unit is increased, the compression force of the compression roller does not decrease as in the conventional case, and it is possible to provide a recycled pellet manufacturing device and a twisted cord manufacturing device that do not cause quality deterioration problems. [Brief description of the drawings]

[0028] [Figure 1] 1 is a front view showing an example of a recycled pellet manufacturing apparatus according to the present invention. [Diagram 2] FIG. 2 is a plan view of the embodiment shown in FIG. [Diagram 3] FIG. 2 is a cross-sectional view showing a main part of a rotary compression section. [Figure 4] 1A is a diagram showing the force acting on the pressure-side compression roller, and FIG. [Diagram 5] FIG. 2 is a diagram showing an example of a twisted cord manufacturing apparatus. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] An embodiment of the present invention will now be described with reference to the drawings. A recycled pellet manufacturing apparatus 10 according to the present invention is roughly composed of a loss film supply section 12, a rotary compression section 14, and a cutting section 16, as shown in Figs.

[0030] The loss film supply unit 12, which has a pair of upper and lower pinch rollers 18a and 18b, is a unit that sends one or more loss films R1 together and sends them to the rotary compression unit 14 described below. In this embodiment, the loss film R1 is supplied in-line from a film forming machine (not shown), but the loss film R1 may also be wound around a reel (not shown) as a supply source.

[0031] The pinch rollers 18a and 18b are the starting point K for twisting the loss film R1, and are arranged so that the upper pressure-side pinch roller 18a presses against the lower drive-side pinch roller 18b with a spring (not shown). As a result, the upper pressure-side pinch roller 18a rotates to the driven side by the rotation of the lower drive-side pinch roller 18b. The pressure applied by the pressure-side pinch roller 18a is adjusted by a compression force adjustment mechanism (not shown). If there is no need to adjust the pressure, this does not have to be provided.

[0032] In this embodiment, the loss film R1 is clamped by a pair of pinch rollers 18a and 18b, and this clamped portion serves as the twist starting point K. The twist starting point K is not limited to the clamped portion, and for example, a dancer roll (not shown) that applies tension to the loss film R1 may be provided and used as the twist starting point K.

[0033] The rotary compression unit 14 is composed of a rotating unit 20, a compression unit 22 mounted within this rotating unit 20, and a first drive unit 24 and a second drive unit 26 which rotate the rotating unit 20 and the compression unit 22 independently, and these are mounted on a stand 28.

[0034] The rotating portion 20 is constituted by a casing 30 and a first driven pulley 32, and the casing 30 is rotatably attached to the frame 28 via front and rear bearings 34, 36.

[0035] The casing 30 of the rotating section 20 is divided into a front section 30a and a rear section 30b. The front section 30a is cylindrical, and has the first driven pulley 32 and one of the bearings 34 mounted thereon.

[0036] The rear stage 30b is a hollow rectangular box with the front stage 30a integrally projecting from its front end, and the other bearing 36 is attached to a protruding cylindrical support portion 30c at the outlet portion.

[0037] The compression section 22 is made up of upper and lower compression rollers 38a and 38b, upper and lower feed rollers 40a and 40b, a hollow main gear member 44 to which a second driven pulley 42 is attached, and a gear train 46 (FIG. 2) made up of a plurality of gears that mesh with the main gear member 44 and rotate the drive-side compression roller 38b and the drive-side feed roller 40b. Either of the compression rollers 38a and 38b and the feed rollers 40a and 40b may be the drive side.

[0038] The main gear member 44 is composed of a main gear 44a and a hollow shaft portion 44b. The hollow shaft portion 44b is rotatably housed in the front stage portion 30a of the casing 30, and the second driven pulley 42 is attached to the portion protruding outward from the front stage portion 30a.

[0039] A main gear 44 a is provided at the end of the hollow shaft portion 44 b inside the casing 30 , and the main gear 44 a is disposed so as to face a notched window 48 in the casing 30 .

[0040] A driven gear 50 is disposed on the outside of the casing 30 so that a portion of the driven gear 50 enters the casing 30 through the notched window 48 and meshes with the main gear 44 a through the notched window 48 .

[0041] A worm gear 52 is attached to the rotation shaft of the driven gear 50, and a worm wheel 54 is meshed with the worm gear 52. The worm wheel 54 is attached to one end of the rotation shaft 38c of the drive-side compression roller 38b.

[0042] 2, a first transmission gear 56 is attached to the other end of the rotating shaft 38c of the drive-side compression roller 38b, and a third transmission gear 60 is attached to the other end of the rotating shaft 40c of the drive-side feed-out roller 40b. The first transmission gear 56 and the third transmission gear 60 are both meshed with an intermediate second transmission gear 58, and the drive-side feed-out roller 40b is set to rotate slightly faster, about 10%, than the drive-side compression roller 38b via the gear train 46 extending from the first transmission gear 56 to the third transmission gear 60.

[0043] The first driving unit 24 is composed of a first driving motor 62 and a first driving pulley 64 attached to the rotary shaft of the first driving motor 62 , and the first driving pulley 64 and the first driven pulley 32 are connected by a first timing belt 66 .

[0044] The second driving section 26 is composed of a second driving motor 68 and a second driving pulley 70 attached to the rotary shaft of the second driving motor 68 , and the second driving pulley 70 and the second driven pulley 42 are connected by a second timing belt 72 .

[0045] The compression rollers 38a, 38b of the compression section 22 are cylindrical members (or a number of disks with numerous jagged protrusions protruding from their outer periphery stacked into a cylindrical shape) with a number of hemispherical (wart-like) or elliptical protrusions 74, or a trapezoidal protrusion when viewed from the front, formed over the entire surface of their outer surfaces (see circle in Figure 2).

[0046] A rotating shaft 38c is provided at the center of each of the pressure-side compression roller 38a and the drive-side compression roller 38b, and both ends of the rotating shaft 38c are rotatably supported in an elongated hole 30d and a round hole 30e, respectively, of the casing 30 (see FIG. 3). The long axis of the elongated hole 30d faces in the pressure direction of the pressure-side compression roller 38a, allowing the pressure-side compression roller 38a to be slightly displaced in the direction toward or away from the drive-side compression roller 38b.

[0047] A pair of compression force adjustment mechanisms 76 are attached to both sides of the upper pressure-side compression roller 38a on the rotation shaft 38c of the pressure-side compression roller 38a. Each compression force adjustment mechanism 76 applies a pressing force by pressing the pressure-side compression roller 38a toward the drive-side compression roller 38b, and is roughly composed of a cylinder 78, a piston 80, a spring 82, and a cover 84.

[0048] The cylinder 78 is a cylindrical member with a bottom, and is fixed to the casing 30. A lid 84 is attached to its upper opening. A round hole 78a is formed in the bottom surface of the cylinder 78, and a rod 80a of a piston 80 housed in the cylinder 78 protrudes to the outside through this round hole 78a. The protruding end of the rod 80a is connected to the rotation shaft 38c of the pressure-side compression roller 38a.

[0049] A spring 82 is accommodated in the piston 80 in a deflected state, and the resilient force of the spring 82 is transmitted to the pressure-side compression roller 38a via the piston 80. As a result, the compression force adjustment mechanism 76 presses the pressure-side compression roller 38a toward the drive-side compression roller 38b with a strong force.

[0050] A plurality of weights 86 are attached to the rotation shaft 38c of the pressure-side compression roller 38a. In this embodiment, four weights 86 are evenly arranged on both the left and right sides of the pressure-side compression roller 38a and in front and rear of the rotation shaft 38c.

[0051] Here, the position of each weight 86 is set so that the point of application S of the resultant force fc of the centrifugal forces fc1, fc2, ... acting on each weight 86 when the rotary compression section 14 is rotating is located on a straight line L connecting the center of gravity G of the pressure-side compression roller 38a and the center of rotation O of the rotary compression section 14, and on the opposite side of the rotation center O to the pressure-side compression roller 38a (the side of the drive-side compression roller 38b) (in this embodiment, the four weights 86 are arranged in a state where they protrude from the casing 30).

[0052] The weight and distance from the center of rotation O of each weight 86 are appropriately set so that the resultant force fc of the centrifugal forces fc1, fc2, . . . acting on each weight 86 is approximately equal to the centrifugal force Fc of the pressure-side compression roller 38a.

[0053] The point of application S of the resultant force fc of the centrifugal forces fc1, fc2, ... acting on each weight 86 is arranged to be located on the straight line L connecting the center of gravity G of the pressure-side compression roller 38a and the center of rotation O of the rotary compression section 14 in order to make it easier to balance the centrifugal force Fc of the pressure-side compression roller 38a and the centrifugal force fc of the weight 86, and it is not necessary to arrange it on the straight line L.

[0054] The pair of upper and lower delivery rollers 40a, 40b of the compression section 22 are disposed downstream of the compression rollers 38a, 38b, and, like the compression rollers 38a, 38b, their respective rotating shafts 40c are rotatably supported by the casing 30. The rotational force of the drive-side compression roller 38b is transmitted to the drive-side delivery roller 40b by a gear train 46 extending from the first transmission gear 56 to the third transmission gear 60.

[0055] Like the compression rollers 38a and 38b, the feed rollers 40a and 40b are also provided with a compression force adjustment mechanism (not shown) that adjusts the pressure of the upper feed roller 40a, which is the pressurizing side, against the lower feed roller 40b, which is the driving side and which is the pressure receiving side, using a spring (not shown). If there is no need to adjust the pressure, this does not have to be provided.

[0056] The relationship between the driving side compression roller 38b and the driving side pinch roller 18b is set so that the driving side compression roller 38b rotates faster than the driving side pinch roller 18b, so that a force that stretches the loss film R1 transported between the pinch rollers 18a and 18b and the compression rollers 38a and 38b is applied to the loss film R1.

[0057] In the rotary compression unit 14, the casing 30 of the rotating unit 20 and the main gear member 44 of the compressing unit 22 can be rotated independently. First, in the rotating unit 20, the casing 30 is rotated by driving the first drive motor 62 of the first drive unit 24. As a result, twist is applied to the loss film R1 between the pinch rollers 18a and 18b and the compression rollers 38a and 38b to form a twisted cord R2.

[0058] Meanwhile, in the compression section 22, the main gear member 44 is rotated by driving the second drive motor 68 of the second drive section 26. When the main gear member 44 rotates, its rotational force is transmitted to the driven gear 50, the worm gear 52, and the worm wheel 54, and the drive-side compression roller 38b rotates. The twisted string R2 is sandwiched from above and below by the pair of upper and lower compression rollers 38a and 38b, and is strongly compressed by the protrusions 74 on the surfaces of the compression rollers 38a and 38b. As a result, a concave impression Y is imparted to the surface of the twisted string R2, forming a crimped twisted string R3 with a concave impression. In this embodiment, the rotation section 20 and the compression section 22 are operated simultaneously.

[0059] The crimped twisted string R3 with concave indentations formed in the casing 30 of the rotary compression section 14 is sent out from the protruding support section 30c which serves as the outlet section. The crimped twisted string R3 with concave indentations sent out from the rotary compression section 14 to the cutting section 16.

[0060] The cutting section 16 is a section that cuts the crimped twisted cord R3 with concave indentations sent out from the rotary compression section 14, and is broadly composed of a pair of upper and lower take-up rollers 88a and 88b, a cutter 90, a motor 92 with a gearbox, and a recycled pellet collection box 94.

[0061] The take-up rollers 88a and 88b are for taking up the crimped twisted cord R3 with concave indentations sent out from the rotary compression section 14 and sending it to the cutter 90, and are arranged so that the upper pressure side take-up roller 88a presses against the lower drive side take-up roller 88b by a compression force adjustment mechanism (not shown). As a result, the upper pressure side take-up roller 88a rotates to the driven side by the rotation of the lower drive side take-up roller 88b.

[0062] The cutter 90 cuts the crimped twisted cord R3 with concave indentations taken up by the take-up rollers 88a and 88b, and its rotating shaft 90a is connected to a variable speed motor 92. The rotation speed of the cutter 90 can be changed as desired by adjusting the rotation speed of the variable speed motor 92, and is set appropriately taking into consideration the feed speed of the crimped twisted cord R3 with concave indentations and the target size of the recycled pellets P.

[0063] A recycled pellet recovery box 94 is provided at the lower end of the cutter 90, and recycled pellets P formed by cutting the crimped twisted string R3 with concave impressions with the cutter 90 fall under their own weight and are stored in the recycled pellet recovery box 94.

[0064] Next, a method for manufacturing recycled pellets P using this recycled pellet manufacturing apparatus 10 will be described. First, one or more wide loss films R1 as raw material are set as specified between the pinch rollers 18a and 18b of the loss film supply unit 12. When there are multiple wide loss films R1, they are pulled together, stacked one on top of the other, and their tips are lightly twisted to form a bundle.

[0065] Next, this loss film R1 is passed through the hollow shaft portion 44b of the main gear member 44 in the rotary compression section 14, and its insertion end is inserted between the pair of compression rollers 38a and 38b and between the delivery rollers 40a and 40b in that order (the loss film R1 passes through the center of the casing 30). The insertion end pulled out from the support portion 30c of the casing 30 is then sandwiched between the take-up rollers 88a and 88b, thereby completing the setting of the loss film R1.

[0066] Once the setting of the loss film R1 is completed as described above, the power is turned on for the recycled pellet manufacturing apparatus 10. When the power of the recycled pellet manufacturing apparatus 10 is turned on, the rotating section 20 and the compressing section 22 of the rotary compressing section 14 start operating simultaneously.

[0067] First, the movement of the rotating part 20 will be described. When the rotating part 20 starts to drive, the casing 30 starts to rotate. This starts the "twisted string forming process" in which the loss film R1 is twisted to form the twisted string R2. Since the loss film R1 passes through the center of the casing 30, the casing 30 rotates around the loss film R1 as the center of rotation.

[0068] (Twisted cord formation process) In the twisted cord forming process, the first drive motor 62 of the first drive unit 24 is driven. When the first drive motor 62 rotates, its rotational force is transmitted to the front section 30a of the casing 30 via the first timing belt 66 and the first driven pulley 32, and the casing 30 starts to rotate around the loss film R1. When the casing 30 rotates, the compression rollers 38a and 38b mounted inside the casing 30 also rotate together with the casing 30.

[0069] The loss film R1 is sandwiched from above and below between the pinch rollers 18a and 18b and the compression rollers 38a and 38b, and in this state the compression rollers 38a and 38b rotate together with the rotation of the casing 30. As a result, the loss film R1 between the pinch rollers 18a and 18b and the compression rollers 38a and 38b is twisted with the pinch point between the pinch rollers 18a and 18b serving as the twist starting point K, to become a twisted cord R2.

[0070] In the twisted cord forming process, in this embodiment, the casing 30 is set to rotate 5 to 10 times per second, so that a sufficient twist is applied to the wide loss film R1 between the pinch rollers 18a and 18b and the compression rollers 38a and 38b, forming a tight, thin twisted cord R2.

[0071] Meanwhile, in the compression section 22, the compression rollers 38a and 38b rotate, drawing the twisted string R2 into the rotary compression section 14 and point-crimping it to form a crimped twisted string R3 with a concave impression (point crimping process), and then sending out this crimped twisted string R3 with a concave impression towards the cutting section 16 (sending out process).

[0072] (Point crimping process) In the point bonding process, the operation of the second drive unit 26 is started. When the second drive motor 68 of the second drive unit 26 starts rotating, the rotational force is transmitted to the main gear member 44 via the second timing belt 72 and the second driven pulley 42, and the main gear member 44 starts rotating. Then, the main gear 44a of the main gear member 44 rotates the side driven gear 50, which rotates the drive-side compression roller 38b in the feed direction of the twisted cord R2 via the worm gear 52 and the worm wheel 54.

[0073] Since the pressure-side compression roller 38a is pressed strongly against the drive-side compression roller 38b by the elastic force of the spring 82 of the compression force adjustment mechanism 76, both the drive-side compression roller 38b and the pressure-side compression roller 38a rotate in the feed direction of the twisted string R2, drawing the twisted string R2 into the rotary compression section 14 at high speed.

[0074] The twisted cord R2 is tightly clamped between the pair of upper and lower compression rollers 38a and 38b with a predetermined pressing force (pressing force Fk of the compression force adjustment mechanism 76), so that at the same time as the twisted cord R2 is pulled into the rotary compression section 14, the protrusions 74 formed on the outer circumferential surface of the twisted cord R2 continuously form deep concave indentations Y on both the upper and lower surfaces, and the twisted cord R2 is point-bonded to become a crimped twisted cord R3 with concave indentations. In the crimped twisted cord R3 with concave indentations, the films are firmly crimped together by the concave indentations Y.

[0075] Here, for the rotary compression section 14, which is a rotating body, it is necessary to take into consideration the "centrifugal force due to rotation" as described in the prior art. That is, in the rotary compression section 14 during rotation, the pressure-side compression roller 38a is subjected to the centrifugal force Fc of the pressure-side compression roller 38a in addition to the pressing force Fk by the compression force adjustment mechanism 76 described above. In addition, since the weight 86 is connected to the pressure-side compression roller 38a, the centrifugal force fc of the weight 86 also acts on the pressure-side compression roller 38a. This point will be described below with reference to FIG. 4.

[0076] First, the pressing force Fk of the compression force adjustment mechanism 76 is a force acting on the pressure-side compression roller 38a by the resilience of the spring 82 of the compression force adjustment mechanism 76, and the direction of the force acting is from the pressure-side compression roller 38a toward the drive-side compression roller 38b (this direction coincides with the direction from the center of gravity G of the pressure-side compression roller 38a toward the rotation center O of the rotary compression section 14). When a plurality of compression force adjustment mechanisms 76 are provided as in this embodiment, the pressing force Fk of the compression force adjustment mechanism 76 is the sum of the pressing forces Fk1, Fk2 of the compression force adjustment mechanisms 76 (Fk=Fk1+Fk2).

[0077] Next, the centrifugal force Fc acting on the pressure-side compression roller 38a will be described. The centrifugal force Fc acting on the pressure-side compression roller 38a due to the rotational motion of the rotary compression unit 14 acts on the pressure-side compression roller 38a in a direction from the rotation center O of the rotary compression unit 14 toward the center of gravity G of the pressure-side compression roller 38a, which is the opposite direction to the pressing force Fk by the compression force adjustment mechanism 76 described above.

[0078] Next, we will explain the centrifugal force fc of the weights 86. In this embodiment, four weights 86 are evenly arranged on both the left and right sides of the pressure-side compression roller 38a and in front and behind the rotation shaft 38c. Centrifugal forces fc1, fc2, fc3, and fc4 due to the rotational motion of the rotary compression unit 14 act on each weight 86.

[0079] The point of application S of the resultant force fc of the centrifugal forces fc1, fc2, fc3, and fc4 acting on each of these weights 86 is set to be located on a straight line L passing through the center of gravity G of the pressure-side compression roller 38a and the center of rotation O of the rotary compression section 14, and on the opposite side of the pressure-side compression roller 38a (the side of the drive-side compression roller 38b) across the center of rotation O, and the direction in which the centrifugal force fc of all four weights 86 acts is the exact opposite direction to the centrifugal force Fc of the pressure-side compression roller 38a (the same direction as the pressing force Fk of the compression force adjustment mechanism 76).

[0080] Since the magnitude of the centrifugal force fc of the entire weight 86 is set to be the same as the centrifugal force Fc of the pressure-side compression roller 38a, the centrifugal force Fc of the pressure-side compression roller 38a is offset by the centrifugal force fc of the entire weight 86. In other words, the pressing force Fk of the compression force adjustment mechanism 76 is not reduced by the rotational motion of the rotary compression unit 14 (regardless of its rotational speed).

[0081] In the compression rollers 38a and 38b, the projections 74 formed on the outer circumferential surfaces of the compression rollers 38a and 38b penetrate deeply into the crimped twisted cord R3 with the concave indentations, so that the crimped twisted cord R3 with the concave indentations gets caught in the compression rollers 38a and 38b and is difficult to feed out. Therefore, the feed rollers 40a and 40b feed the crimped twisted cord R3 with the concave indentations toward the cutting section 16 (feed-out process).

[0082] In this embodiment, the "twisted cord forming process" and the "point bonding process" are performed simultaneously when the recycled pellet manufacturing apparatus 10 starts operating, but the "point bonding process" may also be performed after the "twisted cord forming process".

[0083] (Sending process) A first transmission gear 56 is attached to the other end of the drive-side compression roller 38b, and a third transmission gear 60 attached to the drive-side feed-out roller 40b rotates via a second transmission gear 58. The pressure-side feed-out roller 40a presses the crimped twisted cord R3 with concave indentations against the drive-side feed-out roller 40b with a constant pressure while clamping the crimped twisted cord R3 with concave indentations, so the pressure-side feed-out roller 40a also rotates in the feed direction and feeds the crimped twisted cord R3 with concave indentations toward the cutting section 16.

[0084] The feed rollers 40a, 40b rotate in the feed direction slightly faster than the compression rollers 38a, 38b, and therefore apply tension to and pull up the crimped twisted cord R3 with concave indentations, which is sandwiched between the compression rollers 38a, 38b and difficult to pull out because the protrusions 74 are deeply embedded in the concave indentations Y. As a result, the crimped twisted cord R3 with concave indentations is smoothly pulled out from between the compression rollers 38a, 38b and sent out from the support portion 30c of the casing 30 towards the cutting portion 16, where the crimped twisted cord R3 with concave indentations is cut (cutting process).

[0085] (cutting process) The crimped twisted cord R3 with concave indentations sent out from the rotary compression unit 14 is taken up by take-up rollers 88a and 88b of the cutting unit 16. The take-up rollers 88a and 88b start driving simultaneously with the compression rollers 38a and 38b and the delivery rollers 40a and 40b described above.

[0086] The torque motors 88c of the take-up rollers 88a and 88b are controlled to constantly apply a constant torque to the crimped twisted cord R3 with concave indentations sent out from the rotary compression section 14 while taking it up. Therefore, the crimped twisted cord R3 with concave indentations sent out from the rotary compression section 14 is continuously taken up by the take-up rollers 88a and 88b in a taut state (tensioned state) without slack between the delivery rollers 40a and 40b of the rotary compression section 14 and the take-up rollers 88a and 88b.

[0087] The crimped twisted cord R3 with concave indentations taken up by the take-up rollers 88a and 88b is continuously cut by the rotation of the cutter 90 to successively form recycled pellets P. The recycled pellets P cut by the cutter 90 fall under their own weight and are successively stored in a recycled pellet recovery box 94.

[0088] The crimped twisted string R3 with concave indentations Y is cut at intervals that include at least one concave indentation Y, preferably at intervals wider than the intervals between the concave indentations Y formed on its surface, to form regenerated pellets P.

[0089] According to the recycled pellet manufacturing apparatus 10 of this embodiment, a weight 86 is attached to the pressure-side compression roller 38a, and the centrifugal force fc of this weight 86 acts to cancel the centrifugal force Fc of the pressure-side compression roller 38a. Therefore, even if the rotary compression section 14 rotates, the pressing force Fk of the compression rollers 38a and 38b is not weakened as in the conventional case, and the problem of deterioration in the quality of the recycled pellets P does not occur.

[0090] In the above embodiment, the magnitude of the centrifugal force fc of the entire weight 86 is set to be approximately equal to the centrifugal force Fc of the pressure-side compression roller 38a, but the magnitude of the centrifugal force fc of the entire weight 86 may be set to be greater than the centrifugal force Fc of the pressure-side compression roller 38a. In this case, the pressing force Fk of the compression force adjustment mechanism 76 is applied by adding a force (fc-Fc) obtained by subtracting the force of the pressure-side compression roller 38a from the centrifugal force fc of the entire weight 86. In other words, the compression rollers 38a and 38b can press the twisted string R2 with a greater pressing force to form recycled pellets P with a higher density.

[0091] In the above embodiment, a case where a plurality of (four) weights 86 are provided has been described, but the number is not limited to four, and may be one, or two or more. In any case, however, the application point S of the centrifugal force fc acting on the weight 86 (the application point S of the resultant force of the centrifugal forces fc1, f2, ... in the case where a plurality of weights 86 are provided) is set to be located on a straight line L passing through the center of gravity G of the pressure-side compression roller 38a and the center of rotation O of the rotary compression section 14, and on the opposite side of the pressure-side compression roller 38a with the center of rotation O in between.

[0092] Also, as in the prior art, a heating section and an intermediate feed section (not shown) may be provided between the loss film supply section and the rotary compression section (in this case, the intermediate roller of the intermediate feed section becomes the "twist starting point K" of the loss film).

[0093] It is also possible to remove the cutting section 16 from the above-mentioned recycled pellet manufacturing apparatus 10 and use the resulting apparatus consisting of the loss film supply section 12 and the rotary compression section 14 as a twisted cord manufacturing apparatus 100 (see FIG. 5).

[0094] The twisted string R2 formed by the twisted string manufacturing apparatus 100 has a high density and is not easily stretched even when pulled, so it can be used as a packing string or a string for handicrafts. Of course, the twisted string manufacturing apparatus 100 can also be used as a means for reducing the volume of cutting waste (this is also true of the recycled pellet manufacturing apparatus 10).

[0095] When the twisted string R2 is used as a packing string, the concave indentations Y formed on the surface of the twisted string R2 function as a "non-slip" string. When the twisted string R2 is used as a string for handicrafts, the concave indentations Y function as a "pattern" and greatly enhance the design. [Explanation of symbols]

[0096] 10: recycled pellet manufacturing device, 12: loss film supply section, 14: rotary compression section, 16: cutting section, 18a-18b: pinch rollers, 20: rotating section, 22: compression section, 24: first driving section, 26: second driving section, 28: frame, 30: casing, 30a: front section, 30b: rear section, 30c: support section, 30d: long hole, 30e: round hole, 32: first driven pulley, 34: bearing, 36: bearing, 38a: pressure side compression roller, 3 8b: drive side compression roller, 38c: rotating shaft, 40a: pressure side delivery roller, 40b: drive side delivery roller, 40c: rotating shaft, 42: second driven pulley, 44: main gear member, 44a: main gear, 44b: hollow shaft portion, 46: gear train, 48: notch window, 50: driven gear, 52: worm gear, 54: worm wheel, 56: first transmission gear, 58: second transmission gear, 60: third transmission gear, 62: first drive motor, 64: first drive Pulley, 66: first timing belt, 68: second drive motor, 70: second drive pulley, 72: second timing belt, 74: protrusion, 76: compression force adjustment mechanism, 78: cylinder, 78a: round hole, 80: piston, 80a: rod, 82: spring, 84: cover, 86: weight, 88a-88b: take-up roller, 88c: torque motor, 90: cutter, 90a: rotating shaft, 92: variable speed motor, 94: recycled pellet collection box , 100: twisted cord manufacturing device, Fk: pressing force by compression force adjustment mechanism, Fc: centrifugal force of pressure side compression roller, fc: centrifugal force of weight, G: center of gravity of pressure side compression roller, K: starting point (of twisting), L: straight line connecting the center of gravity of pressure side compression roller and the center of rotation of the rotary compression section, O: center of rotation of the rotary compression section, P: recycled pellets, R1: loss film, R2: twisted cord, R3: crimped twisted cord with concave indentation, S: point of action of centrifugal force acting on weight, Y: concave indentation

Claims

1. A recycled pellet manufacturing device (10) comprising: a loss film supplying section (12) that sends out one or more loss films (R1) as a bundle and serves as a starting point (K) for twisting the loss films (R1); a rotary compression section (14) that twists the loss films (R1) sent from the loss film supplying section (12) and point-presses the loss films (R1) to give them a concave impression (Y) to form a crimped twisted string (R3) with a concave impression; and a cutting section (16) that cuts the crimped twisted string (R3) with a concave impression sent out from the rotary compression section (14) to a predetermined length, The rotary compression section (14) has a rotary section (20) that rotates around the loss film (R1) as a rotation axis, and a compression section (22) installed in the rotary section (20), the compression section (22) includes a drive-side compression roller (38b), a pressure-side compression roller (38a) that is displaceable in a direction toward or away from the drive-side compression roller (38b) and cooperates with the drive-side compression roller (38b) to hold the loss film (R1), a compression force adjustment mechanism (76) that presses and urges the pressure-side compression roller (38a) toward the drive-side compression roller (38b), and one or more weights (86) attached to the pressure-side compression roller (38a); The recycled pellet manufacturing apparatus (10) is characterized in that a point of action (S) of the centrifugal force (fc) acting on the weight (86) or a point of action (S) of the resultant force (fc) of each centrifugal force (fc1, fc2, ...) acting on a plurality of weights (86) is located on the drive side compression roller (38b) side relative to the center of rotation (O) of the rotary compression section (14).

2. The recycled pellet manufacturing device (10) according to claim 1, characterized in that the magnitude of the centrifugal force (fc) acting on the weight (86) is set to be equal to or greater than the centrifugal force (Fc) acting on the pressure-side compression roller (38a).

3. The recycled pellet manufacturing apparatus (10) according to claim 1 or 2, characterized in that the point of action (S) of the centrifugal force (fc) acting on the weight (86) or the point of action (S) of the resultant force (fc) of each centrifugal force (fc1, fc2, ...) acting on multiple weights (86) is located on a straight line (L) passing through the center of gravity (G) of the pressure side compression roller (38a) and the center of rotation (O) of the rotary compression section (14).

4. A twisted cord manufacturing apparatus (100) including a loss film supplying section (12) that sends out one or more loss films (R1) as a bundle and serves as a starting point (K) for twisting the loss films (R1), and a rotary compression section (14) that imparts a twist to the loss film (R1) sent from the loss film supplying section (12) and point-presses the same to impart a concave impression (Y) to form a crimped twisted cord (R3) with a concave impression, The rotary compression section (14) has a rotary section (20) that rotates around the loss film (R1) as a rotation axis, and a compression section (22) installed in the rotary section (20), the compression section (22) includes a drive-side compression roller (38b), a pressure-side compression roller (38a) that is displaceable in a direction toward or away from the drive-side compression roller (38b) and cooperates with the drive-side compression roller (38b) to hold the loss film (R1), a compression force adjustment mechanism (76) that presses and urges the pressure-side compression roller (38a) toward the drive-side compression roller (38b), and one or more weights (86) attached to the pressure-side compression roller (38a); A twisted cord manufacturing apparatus (100) characterized in that a point of application (S) of a centrifugal force (fc) acting on the weight (86) or a point of application (S) of a resultant force (fc) of each centrifugal force (fc1, fc2, ...) acting on a plurality of weights (86) is located on the drive-side compression roller (38b) side relative to the center of rotation (O) of the rotary compression section (14).

5. The twisted cord manufacturing apparatus (100) according to claim 4, characterized in that the magnitude of the centrifugal force (fc) acting on the weight (86) is set to be equal to or greater than the centrifugal force (Fc) acting on the pressure-side compression roller (38a).

6. 6. The twisted cord manufacturing apparatus (100) according to claim 4 or 5, characterized in that a point of application (S) of the centrifugal force (fc) acting on the weight (86) or a point of application (S) of the resultant force (fc) of each centrifugal force (fc1, fc2, ...) acting on a plurality of weights (86) is located on a straight line (L) passing through the center of gravity (G) of the pressure-side compression roller (38a) and the center of rotation (O) of the rotary compression section (14).

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