JP5548209B2 - Bead manufacturing method and manufacturing apparatus - Google Patents

Description

  The present invention relates to a method and an apparatus for manufacturing a bead used for a pneumatic tire.

  FIG. 9 is a meridional sectional view of a bead portion in a general pneumatic tire. A bead portion 1 shown in FIG. 9 is a portion provided on the inner side in the tire radial direction of a sidewall portion (not shown), and includes a bead core 2 and a bead filler 3. The bead core 2 is a so-called single wind structure in which a single bead wire 120 is wound a plurality of times to form an annular shape. The bead filler 3 is a rubber material for reinforcing the bead core 2. A pair of bead portions 1 configured as described above are provided so as to be symmetrical about the tire equator plane. A carcass 5 is wound around the pair of bead portions 1 and 1 in a toroidal shape. Here, the carcass 5 is composed of a plurality of carcass cords arranged in parallel and covered with a rubber material, and both ends of the carcass 5 around the bead core 1 from the inner side in the tire width direction to the outer side in the tire width direction as shown in FIG. Wrapped towards.

  FIG. 10 is a perspective view showing a part of the bead core 2 shown in FIG. The bead core 2 is formed by annularly winding a single bead wire 120 a plurality of times. The bead core 2 has a structure in which the winding start end portion 150 and the winding end end portion 160 of the bead wire 120 are wound so as to overlap each other as shown in FIG. 10, in order to prevent the winding of the wound bead wire 120. In addition, the binding yarn 140 is spirally wound around a region where the winding start end portion 150 and the winding end end portion 160 overlap and in the vicinity thereof (see, for example, Patent Document 1).

JP 2004-345537 A

  As shown in FIG. 10, the winding start end 150 of the bead wire 120 is located on the inner peripheral side of the bead core 2. For this reason, a step is formed on the inner peripheral surface of the bead core 2 that is convex inward in the tire radial direction. Hereinafter, the extended region from the end surface at the winding start end 150 of the bead wire 120 and the vicinity of the end surface are referred to as “stepped portion 170”. FIG. 11 is a diagram schematically showing the vicinity of the stepped portion 170 of the bead core 2. In FIG. 11, reference numerals 5a and 5A indicated by broken lines are a plurality of carcass cords constituting the carcass 5 shown in FIG.

As shown in FIG. 9, the carcass 5 is folded back from the inner side in the tire width direction toward the outer side in the tire width direction so as to be in contact with the inner peripheral surface of the bead core 2, but on the inner peripheral surface of the bead core 2. As shown in FIG. 11, since the step portion 170 is formed, a gap is generated between the carcass 5 and the bead core 2 in the step portion 170. That is, as shown in FIG. 11, a gap with a length Δ ₀ is generated between the carcass cord 5 </ b> A disposed in the stepped portion 170 and the bead core 2.

  At the time of vulcanization of the raw tire, the carcass 5 is pulled in the direction of the arrow D shown in FIG. 9, that is, in the tire width direction inner side in the tire radial direction, so that tension is applied to each carcass cord 5a. At this time, as shown in FIG. 11, the carcass cord 5A disposed in the stepped portion 170 is displaced in the direction of the arrow E shown in FIG. 11, and accordingly, a portion of the carcass cord 5A on the inner side in the tire width direction is loosened. Arise. As a result, in the vicinity of the side tread portion (not shown), the so-called “end disturbance” in which the intervals of the carcass cords are uneven is likely to occur. In particular, when carcass cord openings occur, strain concentrates where the openings occur while the vehicle is running, causing cracks in the inner liner (not shown) and reducing tire durability. There is a risk.

  The present invention has been made in view of the above, and provides a method and apparatus for manufacturing a bead having a function of preventing end disturbance of a carcass cord caused by a step portion generated by a winding start end portion of a bead wire. With the goal.

  In order to solve the above-described problems and achieve the object, a method for manufacturing a bead according to the present invention includes a bead wire bundle formed in an annular shape by winding a single bead wire a plurality of times by a support roller. In the method for manufacturing a bead having a yarn winding step of spirally winding a binding yarn around the bead wire bundle by rotating a winding device in a cross-sectional circumferential direction of the bead wire bundle while rotating in the direction, the winding of the bead wire in the bead wire bundle The winding speed of the support roller is controlled so that the rotation speed of the support roller is slower than that when the binding thread is wound around a region other than the step portion while the binding yarn is wound around the step portion generated by the start end portion. Or the winding speed of the winding device winds the binding yarn around an area other than the stepped portion. The binding yarn is wound at a smaller pitch than the region other than the stepped portion by controlling the rotational speed of the winding device so as to be faster than the case or at least one of the control. It is characterized by.

  According to this bead manufacturing method, a bead having the function of reducing the amount of the step by winding the binding yarn around the step to a high density and preventing the end disturbance of the carcass cord due to the step is manufactured. can do.

  In the bead manufacturing method according to the present invention, in the yarn winding step, the time required for the bead wire bundle to rotate is calculated in advance as the distance from the winding start position of the binding yarn to the end of the stepped portion, The control is performed when the time has elapsed from the start time of winding the binding yarn around the bead wire bundle.

  According to this bead manufacturing method, it is possible to manufacture a bead having a function of reducing the amount of the step and preventing end disturbance of the carcass cord due to the step portion.

  In the bead manufacturing method according to the present invention, in the yarn winding step, the distance from the winding start position of the binding yarn to the end of the stepped portion is calculated in advance, and the bead wire bundle is only the distance from the winding start position. If it rotates, the control is performed.

  According to this bead manufacturing method, it is possible to manufacture a bead having a function of reducing the amount of the step and preventing end disturbance of the carcass cord due to the step portion.

  The bead manufacturing method according to the present invention is characterized in that a sensor for detecting a winding start end of a bead wire is disposed at a predetermined position, and the control is performed based on a detection result of the sensor in the bobbin winding step. To do.

  According to this bead manufacturing method, it is possible to manufacture a bead having a function of reducing the amount of the step and preventing end disturbance of the carcass cord due to the step portion.

  The bead manufacturing apparatus according to the present invention includes a support roller that supports a bead wire bundle formed in an annular shape by winding a single bead wire a plurality of times so as to be rotatable in a circumferential direction of the bead wire bundle, and the support roll. A winding device that winds a binding yarn around the bead wire bundle while rotating in the circumferential direction of the cross section of the supported bead wire bundle, and the bead wire bundle is rotated by rotating the winding device while rotating the bead wire bundle by the support roller. In the bead manufacturing apparatus having a thread winding device configured to spirally bind the binding yarn, the thread winding device includes a first driving device that rotates the support roller, and a second device that rotates the winding device. A driving device; and a control device that controls the first driving device and the second driving device. The control device is compared with the case where the winding device winds the rotation speed of the support roller around a region other than the step portion while the binding device winds the binding thread around the step portion generated by the winding start end portion of the bead wire in the bead wire bundle. The first drive device is controlled so as to be slower, or the second drive device is controlled so that the rotational speed of the winding device is faster than when winding around an area other than the stepped portion. Alternatively, the binding yarn is wound at a pitch smaller than that of the region other than the stepped portion by controlling at least one of them.

  According to this bead manufacturing apparatus, a bead having a function of reducing the amount of the step by winding the binding yarn around the step to a high density and preventing end disturbance of the carcass cord due to the step is manufactured. can do.

  Further, in the bead manufacturing apparatus according to the present invention, the control device calculates in advance the time required for the bead wire bundle to rotate, the distance from the winding start position of the binding yarn to the end of the stepped portion, The control is performed when the time has elapsed from the start time of winding the binding yarn around the bead wire bundle.

  According to this bead manufacturing apparatus, it is possible to manufacture a bead having a function of reducing the amount of the step and preventing end disturbance of the carcass cord caused by the step.

  In the bead manufacturing apparatus according to the present invention, the control device calculates in advance a distance from the winding start position of the binding yarn to the end of the stepped portion, and the bead wire bundle is calculated from the winding start position by the distance. If it rotates, the control is performed.

  According to this bead manufacturing apparatus, it is possible to manufacture a bead having a function of reducing the amount of the step and preventing end disturbance of the carcass cord caused by the step.

  The bead manufacturing apparatus according to the present invention includes a sensor that detects a winding start end of a bead wire, and the control device performs the control based on a detection result of the sensor.

  According to this bead manufacturing apparatus, it is possible to manufacture a bead having a function of reducing the amount of the step and preventing end disturbance of the carcass cord caused by the step.

  In the bead manufacturing method and manufacturing apparatus according to the present invention, the binding yarn is spirally formed in the bead wire bundle by rotating the winding device in the circumferential direction of the cross section of the bead wire bundle while rotating the bead wire bundle in the circumferential direction by the support roller. In the method and apparatus for winding the wire, the rotational speed of the support roller is slowed or the rotational speed of the winding device is increased while winding the binding yarn around the step formed by the winding start end of the bead wire in the bead wire bundle, or at least By performing control of either one, the binding yarn is wound with a smaller pitch than the region other than the stepped portion. According to the bead manufacturing method and the manufacturing apparatus according to the present invention, the amount of the step is reduced by winding the binding yarn around the step portion with high density, and the end disorder of the carcass cord due to the step portion is prevented. A bead having a function can be manufactured.

FIG. 1 is a schematic perspective view showing a part of a bead core manufactured by a bead manufacturing method and a manufacturing apparatus according to the present embodiment. FIG. 2 is a schematic view of the vicinity of the step portion of the bead core shown in FIG. FIG. 3A is a schematic configuration diagram of a bobbin winding device in a bead manufacturing apparatus. FIG. 3-2 is a schematic configuration diagram of a bobbin winding device in the bead manufacturing apparatus. FIG. 4-1 is a schematic configuration diagram of a bobbin winding device in a bead manufacturing apparatus. FIG. 4-2 is a schematic configuration diagram of a bobbin winding device in a bead manufacturing apparatus. FIG. 5-1 is a schematic configuration diagram of a bobbin winding device in a bead manufacturing apparatus. FIG. 5-2 is a schematic configuration diagram of a bobbin winding device in a bead manufacturing apparatus. FIG. 6A is a schematic configuration diagram of a bobbin winding device in a bead manufacturing apparatus. FIG. 6B is a schematic configuration diagram of a yarn winding device in the bead manufacturing device. FIG. 7 is a partially enlarged view of the bobbin winding device. FIG. 8 is a diagram for explaining an example of control using a sensor. FIG. 9 is a meridional sectional view of a bead portion in a conventional pneumatic tire. FIG. 10 is a schematic perspective view showing a part of a conventional bead core. FIG. 11 is a schematic view of the vicinity of the step portion of the bead core shown in FIG.

  DESCRIPTION OF EMBODIMENTS Embodiments of a bead manufacturing method and a manufacturing apparatus according to the present invention will be described below in detail based on the drawings. The present invention is not limited to the following embodiments. In addition, constituent elements of the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

  In the following description, the tire width direction means a direction parallel to the rotation axis (not shown) of the pneumatic tire, and the inner side in the tire width direction means the side toward the tire equatorial plane in the tire width direction, and the outer side in the tire width direction. The term “side away from the tire equator plane” in the tire width direction. Here, the tire equator plane is a plane orthogonal to the rotational axis of the pneumatic tire and passing through the center of the tire width of the pneumatic tire. The tire equator line is a pneumatic tire on the tire equator plane. A line along the circumferential direction. Further, the tire radial direction refers to a direction orthogonal to the rotation axis, the tire radial inner side is the side toward the rotation axis in the tire radial direction, and the tire radial direction outer side is the side away from the rotation axis in the tire radial direction. Say. The tire circumferential direction is a circumferential direction with the rotation axis as a central axis.

  FIG. 1 is a schematic perspective view showing a part of a bead core 10 manufactured by a bead manufacturing method and a manufacturing apparatus according to the present embodiment. The bead core 10 constitutes the bead portion of the pneumatic tire as described with reference to FIG. 9, and although not shown, the bead core 10 serves to fix the pneumatic tire to the rim flange portion of the wheel, and the pneumatic tire It has a role to support the carcass cord tension generated by the internal pressure of the carcass.

  The bead core 10 is configured by winding a bead wire 14 around a bead wire bundle 13 formed in an annular shape by continuously winding a single bead wire (steel wire) 12 a plurality of times. The cross-sectional shape of the bead wire bundle 13 is, for example, a hexagonal shape or a rectangular shape. The bead wire 12 is wound so that the winding start end portion 15 and the winding end end portion 16 overlap each other, and in order to suppress the bead wire 12 from expanding (separating) in the bead core circumferential direction, the winding start is started. The above-described binding yarn 14 is wound over the end 15, the winding end 16 and the vicinity thereof. The binding yarn 14 is a cord made of an organic fiber such as vinylon (registered trademark) or nylon (registered trademark). The diameter of the binding yarn 14 is smaller than the diameter of the bead wire 12.

  The winding start end 15 of the bead wire 12 is located on the inner peripheral side of the bead core 10 as shown in FIG. Therefore, the winding start end portion 15 causes a step that protrudes inward in the tire radial direction on the inner peripheral surface of the bead core 10. Hereinafter, the extension region from the end surface 18 at the winding start end portion 15 of the bead wire 12 and the vicinity of the end surface 18 are referred to as “stepped portion 17”. As shown in FIG. 1, the winding pitch of the binding yarn 14 in the stepped portion 17 is wound at a high density with a smaller pitch than the winding pitch in the region other than the stepped portion 17. In this way, by winding the binding yarn 14 around the step portion 17 at a high density, the step amount of the step generated by the winding start end portion 15 of the bead wire 12 is reduced. Hereinafter, a portion where the binding yarn 14 is wound around the step portion 17 at a high density is referred to as a “high density winding portion 20”. Further, the winding width of the high-density winding portion 20 is set as the width of the step portion 17.

  FIG. 2 is a schematic view of the vicinity of the stepped portion 17 of the bead core 10 shown in FIG. Hereinafter, functions of the bead core 10 configured as described above will be described. In FIG. 2, reference numeral 5 a indicated by a broken line is a carcass cord constituting a carcass (see FIG. 9) arranged along the bead core 10. The plurality of carcass cords 5 a are arranged at regular intervals along the circumferential direction of the bead core 10. In the stepped portion 17, the carcass cord disposed at the position closest to the end face 18 of the winding start end portion 15 is referred to as “carcass cord 5A”. Hereinafter, the diameter of the carcass cords 5a and 5A will be described as d.

As shown in FIG. 2, in the high-density winding portion 20, the distance L ₀ from the end surface 18 at the winding start end portion 15 of the bead wire 12 to the binding yarn 14 closest to the end surface 18 is within d / 2, and , while satisfying the condition winding pitch L ₁ of the binding yarn 14 is within d / 2, or two turns in the circumferential surface of the bead wire bundle 13 is wrapped (Figure in 2 5 weeks) spiral.

  As described above, when the raw tire is vulcanized, the carcass 5 is pulled in the direction of the arrow D shown in FIG. 9, so that tension is applied to each carcass cord 5a shown in FIG. At this time, as in the conventional bead core 2 shown in FIG. 10, when the binding yarn 14 is wound at the same winding pitch over the entire winding region of the binding yarn 14, it is close to the end surface 180 of the winding start end portion 150. The carcass cord 5A to be displaced is displaced in the direction of arrow E in FIG. 11, and accordingly, the carcass cord 5A is loosened at the inner portion in the tire width direction. As a result, there is a problem that end disturbance of the carcass cord is likely to occur near the side tread portion (not shown) due to the loosening.

On the other hand, in the bead core 10 shown in FIG. 2, the amount of the step formed on the inner peripheral surface of the bead core 10 is reduced by the high-density winding portion 20, so that the carcass cord 5 </ b> A is shown in FIG. 2. And the bead core 10 (binding yarn 14) has a length Δ _{1 that} is smaller (or 0) than Δ ₀ shown in FIG. As a result, even if a tension is applied to the carcass cord 5A during vulcanization, the carcass cord 5A is not loosened as much as the conventional part in the tire width direction. Therefore, it is possible to effectively prevent the end disturbance of the carcass cord due to the stepped portion 17.

Here, if the distance L ₀ shown in FIG. 2 exceeds d / 2, the binding yarn 14 may not exist between the carcass cord 5A and the bead core 10. In this case, since the level difference of the level difference is not different from the conventional level, a gap of length Δ ₀ (see FIG. 11) still exists between the carcass cord 5A and the bead core 10. Therefore, the above-described effect cannot be obtained. The same applies to the case where the winding pitch L ₁ of the binding yarn 14 exceeds d / 2. That is, in the stepped portion 17, when the carcass cord 5A is positioned between the adjacent binding yarns 14 and the binding yarns 14, the binding yarns 14 do not exist, and therefore the step amount is the same as that shown in FIG. Therefore, the above-described effect cannot be obtained. Further, the number of times wound around the binding yarn 14 to the stepped portion 17 is at least twice the width L ₂ wound into the stepped portion 17 is to 4 times approximately twice the diameter d of the carcass cord 5A. Moreover, when the diameter of the binding yarn 14 is extremely small compared to the diameter of the bead wire 12, the binding yarn 14 in the high-density winding portion 20 is wound a plurality of times in the tire radial direction.

  The bead manufacturing method of the present embodiment is a method of manufacturing the bead core 10 shown in FIGS. 1 and 2, and more specifically, the binding yarn 14 to the stepped portion 17 in the winding region of the binding yarn 14. This is a method in which the binding yarn is wound around the step portion 17 at a high density by making the winding pitch of the winding portion smaller than the region other than the step portion. Hereinafter, an example of a bead manufacturing apparatus to which the bead manufacturing method according to the present embodiment is applied will be described.

  The bead manufacturing apparatus includes a winding device (not shown), a bobbin winding device (see FIG. 3), and a bead filler attaching device (not shown). Although not shown, the winding device is a device that forms a bead wire bundle 13 shown in FIG. 1 by winding a single bead wire around a drum a plurality of times. The yarn winding device is a device that forms a bead core 10 (see FIG. 1) by winding a binding yarn 14 (see FIG. 1) around a bead wire bundle 13 formed by a winding device. As shown in FIG. 1, the winding region of the binding yarn 14 is a winding start end 15 and a winding end end 16 of the bead wire 12 and the vicinity thereof. A bead filler sticking device is a device which sticks bead filler 3 (refer to Drawing 9) to bead core 10 formed with a spooling device.

  In the bead manufacturing apparatus, first, in a winding process, a bead wire bundle 13 is formed by winding a single bead wire around a drum of the winding apparatus a plurality of times. The formed bead wire bundle 13 is sent to a thread winding device by a conveying / attaching device (not shown) and set at a predetermined position. Next, in the yarn winding step, the bead core 10 is formed by winding the binding yarn 14 around the bead wire bundle 13 using a yarn winding device. The formed bead core 10 is sent to the bead filler affixing device by the conveying / attaching device and set at a predetermined position. And in a bead filler sticking process, bead filler 3 is stuck on bead core 10 using a bead filler sticking device. A bead is completed by sequentially performing the above three steps. The completed bead is transported and stored in a bead stock device (not shown).

  FIGS. 3-1 to 6-2 are schematic configuration diagrams of the yarn winding device 20 in the bead manufacturing device, showing a state in which the bead wire bundle 13 is set in the yarn winding device 20 and the binding yarn 14 is wound. Yes. 3-1, FIG. 4-1, FIG. 5-1, and FIG. 6-1 are views of the bobbin winding device 20 viewed from a position where the bead wire bundle 13 set in the bobbin winding device 20 faces the front. 2, FIG. 4-2, FIG. 5-2, and FIG. 6-2 are views of FIG. 3-1, FIG. 4-1, FIG. 5-1, and FIG. FIG. 7 is a schematic block diagram showing a part of the thread winding device 20 in an enlarged manner. Hereinafter, the configuration of the bobbin winding device 20 will be described with reference to these drawings.

  As shown in FIGS. 3-1, 3-2, and 7, the bobbin winding device 20 includes a pair of support rollers 21a and 21b, and a support roller drive motor M1 (hereinafter abbreviated as “drive motor M1”). , A yarn supply device 23, a winding device 30, a winding device drive motor M2 (hereinafter referred to as "drive motor M2" for short), and a control device 40 that controls the drive of the drive motor M1 and the drive motor M2. It is prepared for.

  The pair of support rollers 21a and 21b support the bead wire bundle 13 so as to be rotatable in the circumferential direction. In the example shown in FIGS. 3A and 7, the support rollers 21 a and 21 b are arranged one by one at positions on both sides of the winding device 30 and away from the winding device 30. The pair of support rollers 21a and 21b are respectively arranged on the inner peripheral side and the outer peripheral side of the bead wire bundle 13, and are connected to the drive motor M1 via a transmission mechanism (not shown). Then, the drive motor M1 is driven with the support rollers 21a and 21b sandwiching the bead wire bundle 13, and the support rollers 21a and 21b are rotated in the directions shown in FIGS. Rotate in the B direction (circumferential direction of the bead wire bundle 13).

  As shown in FIG. 3A, the yarn supply device 23 includes a yarn unwinding unit 24, a gripping unit 25, and a yarn cutting unit 26. The grasping portion 25 sandwiches and holds the leading end of the binding yarn 14 unwound from the yarn unwinding portion 24. The grip portion 25 is connected to a cylinder (not shown), and can be moved to the vicinity of the center portion of the winding device 30 while holding the binding yarn 14 by driving the cylinder, and along the circumferential direction of the bead wire bundle 13. It is configured to be movable. The yarn cutting unit 26 cuts the bundled yarn that has been wound, and is fixed above the winding device 30.

  The winding device 30 is a device that spirally winds the binding yarn 14 around the terminal portion (winding start end portion 15 and winding end end portion) of the bead wire bundle 13 supported by the support rollers 21a and 21b and the vicinity thereof. The winding device 30 is formed in a hollow disk shape (substantially cylindrical shape), and extends from a part of the peripheral surface of the winding device 30 to the center of the winding device 30 as shown in FIG. An existing cutout groove 31 is provided. Further, as shown in FIG. 3A, a concave groove 32 for winding the binding yarn 14 is provided on the peripheral surface of the winding device 30. Furthermore, an opening (not shown) for introducing the binding yarn 14 into the winding device 30 is provided in a part of the peripheral surface of the winding device 30. The winding device 30 is connected to the drive motor M2 via a transmission mechanism (not shown), and rotates in the direction of arrow C shown in FIG. 3-2 around the center of the disk by driving the drive motor M2.

  The control device 40 controls the drive of the drive motor M1 and the drive motor M2 as shown in FIG. Specifically, when winding the binding yarn 14 around the stepped portion 17, the control device 40 winds the binding yarn 14 at a smaller pitch than the region other than the stepped portion 17 so as to drive the driving motor M <b> 1 and the driving motor M <b> 2. To control. Specific control contents of the control device 40 will be described later. When the binding yarn 14 is wound around an area other than the stepped portion 17, the control unit 40 controls the drive motors M1 and M2 to rotate the support rollers 21a and 21b and the winding device 30 at a constant rotational speed, respectively. doing.

  Next, a description will be given of a bobbin winding process in which the binding yarn 14 is wound around the bead wire bundle 13 by using the bobbin winding device 20 configured as described above. After the winding process is completed, the bead wire bundle 13 is sent to the bobbin winding device 20 by the transport / attachment device. As shown in FIGS. 3A and 3B, the conveying / mounting device inserts the bead wire bundle 13 through the notch groove portion 31 of the winding device 30 and the bottom of the notch groove portion 31 (that is, the center position of the winding device 30). And the bead wire bundle 13 is set on the support rollers 21a and 21b.

  When the bead wire bundle 13 is set on the support rollers 21a and 21b, the yarn winding device 20 drives a cylinder (not shown) to lower the binding yarn 14 as shown in FIGS. The tying yarn 14 held at 25 is introduced into the winding device 30 from an opening (not shown) of the winding device 30. Next, the yarn winding device 20 drives the drive motor M2 through the control device 40 from the state shown in FIG. 4-2 to rotate the winding device 30 in the direction of arrow C, and drives the drive motor M1 to support rollers 21a, 21b is rotated and the bead wire bundle 13 is sent in the arrow B direction. When the winding device 30 is rotated, the binding yarn 14 is guided by the guide portion 33 inside the winding device 30 as shown in FIG. 5B, and the binding yarn 14 is wound around the peripheral surface of the bead wire bundle 13. At the same time, the binding yarn 14 is also guided into the groove 32 on the peripheral surface of the winding device 30 as shown in FIG.

  Further, the grip portion 25 is movable together with the bead wire bundle 13 by driving a cylinder (not shown). Accordingly, by feeding the bead wire bundle 13 in the direction of arrow B while rotating the winding device 30 in the direction of arrow C, the grip portion 25 moves together with the bead wire bundle 13 while applying tension to the binding yarn 14. As a result, as shown in FIG. 6A, the binding yarn 14 is wound spirally around the peripheral surface of the bead wire bundle 13. When the bundling yarn 14 having a required length is guided to the winding device 30, the bundling yarn 14 is cut by the yarn cutting unit 26 as shown in FIG.

  In the above-described yarn winding process, the control device 40 is configured to wind the rotation speed of the support rollers 21 a and 21 b around the region other than the step portion 17 while the winding device 30 winds the binding yarn 14 around the step portion 17 of the bead wire bundle 13. The drive motor M1 is controlled so as to be slower than the drive motor M1, or the drive motor M2 is controlled so that the rotation speed of the winding device 30 is increased as compared with the case of winding around the region other than the stepped portion 17. At least one of the controls is performed. By performing such control, the high density winding part 20 is formed in the step part 17 as shown in FIG. Hereinafter, a specific control example of the control device 40 will be described. In the following control example, a case where the rotation speed of the support rollers 21a and 21b is decreased will be described.

(Control example 1)
In performing winding step, the bead wire bundle 13 a distance to (one end i.e. the step portion 17) fascinated yarn 14 winding start position S ₂ from the winding start position S ₁ dense winding unit 20 rotates (moves) The time T ₁ required for the calculation is calculated in advance. Further, the bead wire bundle 13 rotates (moves) the distance from the winding start position S ₂ of the high-density winding portion 20 to the winding end position S ₃ of the high-density winding portion 20 (that is, the other end of the step portion 17). The required time T ₂ is calculated in advance. In the yarn winding process, when a preset time T ₁ has elapsed from the time when the binding yarn 14 is wound around the bead wire bundle 13, the drive motor M1 is set so that the rotation speed of the support rollers 21a and 21b is reduced. Control. Further, if a preset time T ₂ has elapsed from the time when this control is started, the control of the drive motor M1 is returned to the normal control, the support rollers 21a and 21b are rotated at the normal rotation speed, and the binding yarn 14 Wind to the end of winding. From the above, the winding of the binding yarn 14 around the bead wire bundle 13 is completed, and the bead core 10 shown in FIG. 1 is formed.

(Control example 2)
In performing winding step, it is calculated in advance the distance to the winding start position S ₂ of the dense winding part 20 from the start position S ₁ winding of the binding yarn 14 (i.e. one end portion of the stepped portion 17). Further, the distance from the winding start position S ₂ of the high-density winding part 20 to the winding end position S ₃ of the high-density winding part 20 (that is, the winding width L ₂ of the high-density winding part 20) is calculated in advance. In the yarn winding process, if the bead wire bundle 13 is rotated (moved) from the winding start position S ₁ of the binding yarn 14 to the bead wire bundle 13 by the preset distance L ₃ , the rotation speed of the support rollers 21a and 21b. The drive motor M1 is controlled so as to slow down. Furthermore, if the bead wire bundle 13 is rotated (moved) by a preset distance L ₂ from the point where this control is started, the control of the drive motor M1 is returned to normal, and the support rollers 21a and 21b are rotated at normal rotation speed. Thus, the wrapping yarn 14 is wound up to the winding end position. As described above, the process of winding the binding yarn around the bead wire bundle 13 is completed, and the bead core 10 shown in FIG. 1 is formed.

(Control example 3)
As shown in FIG. 8, the sensor 41 that detects the stepped portion 17 of the bead wire bundle 13 is fixed at a predetermined position, and the above control is performed based on the detection result of the sensor 41. As the sensor 41, a non-contact sensor such as an ultrasonic sensor that detects the distance between the bead wire bundle 13 and the sensor 41, or a contact sensor that detects the stepped portion 17 by contacting the winding start end 15 of the bead wire 12. Etc. are used. FIG. 8 shows an arrangement example of the sensor 41 when a non-contact sensor is used as the sensor 41. In the example shown in FIG. 8, the sensor 41 is arranged so that the distance between the sensor 41 and the winding device 30 is substantially the same as the winding width L ₂ of the high-density winding portion 20. Similarly to the control example 1, the time required for the bead wire bundle 13 to rotate (move) the distance from the winding start position S ₂ of the high-density winding part 20 to the winding end position S ₃ of the high-density winding part 20. T ₂ is calculated in advance. The yarn winding process is started, and the bead wire bundle 13 is rotated in the direction of arrow B as shown in FIG. 8 to wind the binding yarn 14 around the bead wire bundle 13. Here, when the winding start end 15 of the bead wire 12 passes the sensor 41, the sensor 41 detects the winding start end 15 and transmits a detection result to the control device 40. The control device 40 that has received the detection result controls the drive motor M1 so that the rotational speeds of the support rollers 21a and 21b become slow. Further, if a preset time T ₂ has elapsed from the time when this control is started, the control of the drive motor M1 is returned to the normal control, the support rollers 21a and 21b are rotated at the normal rotation speed, and the binding yarn 14 Wind to the end of winding. From the above, the winding of the binding yarn 14 around the bead wire bundle 13 is completed, and the bead core 10 shown in FIG. 1 is formed.

  In the control examples 1 to 3 described above, the case where the high-density winding part 20 is formed by reducing the rotation speed of the support rollers 21a and 21b has been described. When forming, the same conditions as described above are used. Further, when the high-density winding portion 20 is formed by controlling the rotational speeds of both the support rollers 21a and 21b and the winding device 30, the same conditions as described above are used. Which of the rotation speeds of the support rollers 21a and 21b and the winding device 30 is to be changed may be appropriately selected according to the winding condition of the binding yarn 14 and the like.

  In the case of the control for changing the rotation speeds of the support rollers 21a and 21b as in the above control examples 1 to 3, since the rotation speed of the winding device 30 is constant, the load on the yarn is constant and the yarn is not easily broken. . Further, in the case of control for changing the rotational speed of the winding device 30, the feed speed of the bead wire bundle 13 is constant, and the cycle time in the winding process of the binding yarn 14 is not changed.

  In the present embodiment, the bead wire bundle 13 is rotated in the arrow B direction in the bobbin winding process, but the bead wire bundle 13 may be rotated in the opposite direction to the arrow B direction. In this case, the winding direction of the binding yarn 14 is reversed. That is, the binding yarn 14 starts to be wound from the winding end end 16 side of the bead wire, and is wound in the order of the winding start end 15 and the stepped portion 17. Also in this case, the control example 1 and the control example 2 can be applied. Further, when the control using the sensor 41 is performed, the sensor 41 is disposed at substantially the same position as the winding position of the winding device 30. The rest is the same as the control example 3.

  As described above, in the bead manufacturing method and manufacturing apparatus according to the present embodiment, while the binding yarn 14 is wound around the step portion 17 generated by the winding start end portion 15 of the bead wire 12 in the bead wire bundle 13, the support rollers 21a, The bundling yarn 14 is wound at a smaller pitch than the region other than the stepped portion 17 by slowing down the rotational speed of 21b or increasing the rotational speed of the winding device 30. According to the bead manufacturing method and manufacturing apparatus according to the present embodiment, the amount of step 17 is reduced by winding the binding yarn 14 around the step 17 of the bead wire bundle 13 with high density, and the carcass cord resulting from the step 17 is provided. A bead having a function of preventing end disturbance 5a can be manufactured by a simple method.

  As described above, the bead manufacturing method and the manufacturing apparatus according to the present invention can manufacture a bead in which the level difference caused by the winding start end of the bead wire is reduced.

DESCRIPTION OF SYMBOLS 10 Bead core 12 Bead wire 13 Bead wire bundle 14 Bundling yarn 15 (Bead wire) winding start end part 16 (Bead wire) winding end end part 17 Step part 18 End face of winding start end part 20 Thread winding device 21a, 21b Support roller 23 Thread supply device 24 thread unwinding device 25 gripping portion 26 thread cutting portion 30 winding device 31 notch groove portion 32 concave groove 33 guide portion 40 control device 41 sensor

Claims (8)

By rotating a winding device in the circumferential direction of the bead wire bundle while rotating a bead wire bundle formed in an annular shape by winding a single bead wire a plurality of times in the circumferential direction of the bead wire bundle by a support roller, the bead wire In a method for producing a bead having a thread winding process in which a bundled thread is wound spirally around a bundle,
While the binding yarn is wound around the step portion generated by the winding start end portion of the bead wire in the bead wire bundle, the support roller is rotated so that the rotation speed of the support roller is slower than that when the binding yarn is wound around the region other than the step portion. Controlling the rotational speed of the roller, or controlling the rotational speed of the winding device so that the rotational speed of the winding device is faster than when the binding yarn is wound around a region other than the stepped portion, or at least A bead manufacturing method characterized in that the binding yarn is wound at a smaller pitch than in the region other than the stepped portion by performing any one of the controls. In the thread winding step,
Calculate in advance the time required for the bead wire bundle to rotate the distance from the winding start position of the binding yarn to the end of the stepped portion,
The bead manufacturing method according to claim 1, wherein the control is performed when the time has elapsed from a start time of winding the binding yarn around the bead wire bundle. In the thread winding step,
Calculate in advance the distance from the winding start position of the binding yarn to the end of the stepped portion,
The bead manufacturing method according to claim 1, wherein the control is performed when the bead wire bundle is rotated by the distance from the winding start position. A sensor that detects the winding start end of the bead wire is disposed at a predetermined position,
2. The bead manufacturing method according to claim 1, wherein in the bobbin winding step, the control is performed based on a detection result of the sensor. A support roller for supporting a bead wire bundle formed in an annular shape by winding a single bead wire a plurality of times so as to be rotatable in the circumferential direction of the bead wire bundle;
A winding device for winding a binding yarn around the bead wire bundle while rotating in the circumferential direction of the cross section of the bead wire bundle supported by the support roll;
In the bead manufacturing apparatus having a bobbin winding device configured to spirally wind the binding yarn around the bead wire bundle by rotating the winding device while rotating the bead wire bundle by the support roller,
The bobbin winding device
A first driving device for rotating the support roller;
A second driving device for rotating the winding device;
A control device for controlling the first drive device and the second drive device,
The control device includes:
While the winding device winds the binding yarn around the stepped portion formed by the winding start end portion of the bead wire in the beadwire bundle, the rotation speed of the support roller is made slower than when winding the region around the region other than the stepped portion. Control the first driving device, or control the second driving device so as to increase the rotation speed of the winding device compared to the case of winding around the region other than the stepped portion. By performing either control, the bead manufacturing apparatus is characterized in that the binding yarn is wound at a smaller pitch than the region other than the stepped portion. The control device includes:
Calculate in advance the time required for the bead wire bundle to rotate the distance from the winding start position of the binding yarn to the end of the stepped portion,
The bead manufacturing apparatus according to claim 5, wherein the control is performed when the time has elapsed from a start time of winding the binding yarn around the bead wire bundle. The control device includes:
Calculate in advance the distance from the winding start position of the binding yarn to the end of the stepped portion,
6. The bead manufacturing apparatus according to claim 5, wherein the control is performed when the bead wire bundle is rotated by the distance from the winding start position. It has a sensor that detects the winding start end of the bead wire,
The control device includes:
The bead manufacturing apparatus according to claim 5, wherein the control is performed based on a detection result of the sensor.

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