YARN JOINING DEVICE AND YARN JOINING METHOD

Abstract

 An object of the present invention is to make it possible to join yarns, which have been interlaced, together.
A yarn joining device 6 includes an interlacing means 61, a first clamp 62 and a second clamp 63 which are provided on both sides of the interlacing means 61, a movement mechanism 90, and a controller 69. The controller 69 is programmed to execute an elongation-relaxation control of controlling the movement mechanism 90 so as to repeatedly elongate and relax two yarns Y (i.e., yarns Y1 and Y2) gripped by the first clamp 62 and the second clamp 63. The controller 69 is programmed to execute, after the elongation-relaxation control, an interlacing control of controlling the interlacing means 61 so as to interlace the two yarns Y (i.e., yarns Y1 and Y2).

Description

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a yarn joining device and a yarn joining method that are used for joining two yarns together.

[0002] A known yarn joining device (i.e., splicer) is provided for joining ends of yarns of two packages together. For example, Patent Literature 1 (Japanese Laid-Open Patent Publication No. 2000-16704) discloses a yarn joining device including (i) an interlacing means including an air nozzle and (ii) a pair of yarn gripping means (i.e., a clamp in Patent Literature 1) which are provided on both sides of the interlacing means and which are configured to grip yarns.

[0003] The yarn joining device of Patent Literature 1 is configured to join two yarns together by injecting compressed air from the air nozzle to the two yarns, which are gripped by the paired yarn gripping means, and interlacing the two yarns. To be specific, the compressed air is injected to each yarn so as to loosen the fibers of each yarn and to untwist each yarn. To each untwisted yarn, the compressed air is further injected so that the two yarns are tangled with each other. As a result, yarn joining of the two yarns is completed.

SUMMARY OF THE INVENTION

[0004] For example, when the above-described yarn joining device is used for joining yarns such as DTYs (i.e., Draw Textured Yarns) which are tightly interlaced, yarn joining is not properly performed. This is because, even if the compressed air is injected to the yarns such as DTYs, (i) fibers of the yarns having been interlaced are not loosened and thus (ii) interlacing for joining the yarns together cannot be performed.

[0005] An object of the present invention is to provide a yarn joining device and a yarn joining method that make it possible to join yarns, which have been interlaced, together.

[0006] A yarn joining device of the present invention includes: an interlacing means configured to interlace and join two yarns together; a first yarn gripping means and a second yarn gripping means which are able to grip the yarns and which are provided on both sides of the interlacing means; a movement mechanism which is able to move at least one of the first yarn gripping means and the second yarn gripping means; and a controlling means programmed to control the interlacing means, the first yarn gripping means, the second yarn gripping means, and the movement mechanism. In this regard, the controlling means is programmed to execute: a yarn gripping control of controlling the first yarn gripping means and the second yarn gripping means so that the first yarn gripping means and the second yarn gripping means grip the two yarns; an elongation-relaxation control of controlling, after the yarn gripping control, the movement mechanism so as to repeatedly elongate and relax the two yarns gripped by the first yarn gripping means and the second yarn gripping means; and an interlacing control of controlling, after the elongation-relaxation control, the interlacing means so as to interlace the two yarns.

[0007] A yarn joining method of the present invention is a yarn joining method of joining two interlaced yarns together by means of a yarn joining device including: an interlacing means configured to interlace and join the two yarns together; and a first yarn gripping means and a second yarn gripping means which are able to grip the yarns and which are provided on both sides of the interlacing means. In this regard, the yarn joining method includes: a yarn gripping step of causing the first yarn gripping means and the second yarn gripping means to grip the two yarns; after the yarn gripping step, an elongation-relaxation step of moving at least one of the first yarn gripping means and the second yarn gripping means so as to repeatedly elongate and relax the two yarns gripped by the first yarn gripping means and the second yarn gripping means; and an interlacing step of interlacing the two yarns by means of the interlacing means after the elongation-relaxation step.

[0008] According to the present invention, when the yarns having been interlaced are joined together, the two yarns gripped by each yarn gripping means are repeatedly elongated and relaxed before being interlaced by the interlacing means. Because of this, the fibers of each of the two yarns are loosened between the two yarn gripping means so that the two yarns are untwisted. The interlacing means then interlaces the two untwisted yarns so that the two yarns are joined together. It is therefore possible to join the yarns, which have been interlaced, together.

[0009] Preferably, the yarn joining device of the present invention further includes: a first yarn cutting gripping means which is provided between the interlacing means and the first yarn gripping means and which is configured to cut and grip one of the yarns; and a second yarn cutting gripping means which is provided between the interlacing means and the second yarn gripping means and which is configured to cut and grip the other of the yarns. In this regard, the controlling means is able to control the first yarn cutting gripping means and the second yarn cutting gripping means and is programmed to execute, before the interlacing control, a yarn cutting-gripping control of controlling the first yarn cutting gripping means and the second yarn cutting gripping means so that (i) the first yarn cutting gripping means cuts and grips one yarn among the two yarns and (ii) the second yarn cutting gripping means cuts and grips the other yarn among the two yarns.

[0010] Preferably, the yarn joining method of the present invention is the yarn joining method of joining the two interlaced yarns together by means of the yarn joining device further including: a first yarn cutting gripping means which is provided between the interlacing means and the first yarn gripping means and which is configured to cut and grip one of the yarns; and a second yarn cutting gripping means which is provided between the interlacing means and the second yarn gripping means and which is configured to cut and grip the other of the yarns. In this regard, the yarn joining method further includes a yarn cutting-gripping step of causing, before the interlacing step, the first yarn cutting gripping means to cut and grip one yarn among the two yarns and the second yarn cutting gripping means to cut and grip the other yarn among the two yarns.

[0011] Assume that each of the two yarns has an interlacing part (interlaced part) and a part extending from the interlacing part. In this case, the part extending from the interlacing part is referred to as a tail part. Such tail parts of the yarns cause, e.g., uneven dyeing in a textile or a knitted fabric. It is therefore necessary to remove the tail parts before the next step starts. In the present invention, each yarn cutting gripping means is provided between the interlacing means and each yarn gripping means. With this arrangement, before the two yarns are interlaced by the interlacing means, a tail part of each yarn is arranged to be short.

[0012] Preferably, the yarn joining device of the present invention is arranged such that the controlling means is programmed to execute the yarn cutting-gripping control after the elongation-relaxation control.

[0013] Preferably, the yarn joining method of the present invention is arranged such that the yarn cutting-gripping step is executed after the elongation-relaxation step.

[0014]  In the device provided with the two yarn cutting gripping means for removing the tail parts of the two yarns, when the one yarn is cut and gripped by the first yarn cutting gripping means, the one yarn is gripped by the first yarn cutting gripping means and the second yarn gripping means. Similarly, when the other yarn is cut and gripped by the second yarn cutting gripping means, the other yarn is gripped by the second yarn cutting gripping means and the first yarn gripping means. In this regard, the yarns may be repeatedly elongated and relaxed after the one yarn is cut and gripped by the first yarn cutting gripping means and the other yarn is cut and gripped by the second yarn cutting gripping means. In other words, instead of the first yarn gripping means and the second yarn gripping means, (i) the first yarn cutting gripping means and the second yarn gripping means may elongate and relax the one yarn and (ii) the second yarn cutting gripping means and the first yarn gripping means may elongate and relax the other yarn. In this case, the one yarn is elongated and relaxed only by the movement of the second yarn gripping means, and the other yarn is elongated and relaxed only by the movement of the first yarn gripping means. Because of this, the one yarn is untwisted in the vicinity of the second yarn gripping means, and the other yarn is untwisted in the vicinity of the first yarn gripping means. Therefore, the two yarns are unevenly untwisted. As a result, even if the interlacing means interlaces the two unevenly-untwisted yarns, the yarns may not be properly joined together. Furthermore, the one yarn is not sufficiently untwisted at a part gripped by the first yarn cutting gripping means, and the other yarn is not sufficiently untwisted at a part gripped by the second yarn cutting gripping means. This is because each yarn is fixed by a corresponding yarn cutting gripping means. As a result, even if the interlacing means interlaces the two insufficiently-untwisted yarns, the yarns may not be properly joined together. According to the present invention, before being cut and gripped by the respective yarn cutting gripping means, the two yarns gripped by each yarn gripping means are repeatedly elongated and relaxed. Because of this, the two yarns are elongated and relaxed while being gripped by each yarn gripping means. The two yarns are therefore evenly untwisted. The two yarns are cut and gripped by the respective yarn cutting gripping means after being untwisted. Because of this, the two yarns are sufficiently untwisted at parts gripped by the respective yarn cutting gripping means. As a result, the two yarns are further reliably joined together at the time of the interlace by the interlacing means.

[0015] Preferably, the yarn joining device of the present invention is arranged such that the movement mechanism is able to move both of the first yarn gripping means and the second yarn gripping means. Furthermore, in the elongation-relaxation control, the controlling means is programmed to control the movement mechanism so as to move the both of the first yarn gripping means and the second yarn gripping means.

[0016] When the yarns are elongated to the same length by moving only one of the first yarn gripping means and the second yarn gripping means, the one of the first yarn gripping means and the second yarn gripping means has a long moving distance as compared to the case where the both of the first yarn gripping means and the second yarn gripping means are moved. Therefore, the positions of other members need to be adjusted to provide a space required for allowing the one of the first yarn gripping means and the second yarn gripping means to move. This causes the increase in size of the entire device. In the present invention, the two yarns are elongated by moving the both of the first yarn gripping means and the second yarn gripping means. It is therefore unnecessary to arrange the moving distance of each yarn gripping means to be excessively long. This suppresses the increase in size of the device.

[0017] Preferably, the yarn joining device of the present invention is arranged such that, in the elongation-relaxation control, the controlling means is programmed to control the movement mechanism so as to move the at least one of the first yarn gripping means and the second yarn gripping means at a movement speed of 10 to 25 mm/s.

[0018] When each yarn is elongated at a very high speed, each yarn may get damaged. Meanwhile, when each yarn is elongated at a very low speed, each yarn may not be sufficiently untwisted. As a result of diligent study, the inventors of the subject application have found that the interlaced yarns are efficiently untwisted at the above-described movement speed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] 

FIG. 1 is a top view of a yarn joining device of an embodiment.

FIG. 2 shows a step of a yarn joining operation performed by the yarn joining device, with one yarn threaded to a slit.

FIG. 3 shows a step of the yarn joining operation performed by the yarn joining device, with one yarn and the other yarn threaded to the slit.

FIG. 4 shows a step of the yarn joining operation performed by the yarn joining device, with the two yarns gripped by a first clamp and a second clamp.

FIG. 5 shows a step of the yarn joining operation performed by the yarn joining device, with the two yarns elongated by the first clamp and the second clamp.

FIG. 6 shows a step of the yarn joining operation performed by the yarn joining device, with the two yarns released from the first clamp and the second clamp.

FIG. 7 is a top view of a yarn joining device of a first modification.

FIG. 8 shows a step of the yarn joining operation performed by the yarn joining device of the first modification, with one yarn threaded to a slit.

FIG. 9 shows a step of the yarn joining operation performed by the yarn joining device of the first modification, with one yarn and the other yarn threaded to the slit.

FIG. 10 shows a step of the yarn joining operation performed by the yarn joining device of the first modification, with the two yarns gripped by a first clamp and a second clamp.

FIG. 11 shows a step of the yarn joining operation performed by the yarn joining device of the first modification, with one yarn cut and gripped by a first clamp cutter and the other yarn cut and gripped by a second clamp cutter.

FIG. 12 shows a step of the yarn joining operation performed by the yarn joining device of the first modification, with the two yarns elongated by the first clamp and the second clamp.

FIG. 13 shows a step of the yarn joining operation performed by the yarn joining device of the first modification, with the two yarns starting to be interlaced by an interlacing means.

FIG. 14 shows a step of the yarn joining operation performed by the yarn joining device of the first modification, with the two yarns being interlaced by the interlacing means.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(Yarn Joining Device 6)

[0020] The following will describe an embodiment of a yarn joining device related to the present invention. FIG. 1 is a top view of a yarn joining device 6 of the present embodiment. Hereinafter, the left-right direction on the sheet of FIG. 1 is defined as a first direction, and the up-down direction on the sheet is defined as a second direction. Furthermore, the direction perpendicular to the sheet of FIG. 1 is defined as an up-down direction. In this regard, the up-down direction is a vertical direction in which the gravity acts. These definitions of the directions will be suitably used hereinbelow. The yarn joining device 6 includes a splicer 60.

[0021] As shown in FIG. 1, the splicer 60 includes an interlacing means 61, a first clamp 62 (i.e., a first yarn gripping means of the present invention), a second clamp 63 (i.e., a second yarn gripping means of the present invention), a movement mechanism 90 configured to move the first clamp 62 and the second clamp 63, two guides 66 and 67, a main body portion 68, and a controller 69 (i.e., a controlling means of the present invention) . The interlacing means 61, the first clamp 62, the second clamp 63, the movement mechanism 90, and the two guides 66 and 67 are attached to the main body portion 68.

[0022] As shown in FIG. 1, the interlacing means 61 includes a slit 61a, a nozzle (not illustrated), and a nozzle lid (not illustrated). The slit 61a penetrates the interlacing means 61 in the first direction, and each yarn Y is able to run in the slit 61a. The first direction is equivalent to a predetermined direction of the present invention. The nozzle is able to inject compressed air in the second direction. The nozzle lid is openable and closeable as a member covering the slit 61a. The nozzle lid is open so as not to cover the top surface of the slit 61a before each yarn Y is threaded to the slit 61a, and closed so as to cover the slit 61a after each yarn Y is threaded to the slit 61a. The interlacing means 61 is configured to join two yarns Y together by interlacing the yarns Y with use of the compressed air injected from the nozzle to the yarns Y which are threaded to the slit 61a.

[0023] The first clamp 62 is configured to grip each yarn Y threaded to the slit 61a. The first clamp 62 is provided on one side of the interlacing means 61 in the first direction. The first clamp 62 includes a fixed portion 62a and a movable portion 62b. The fixed portion 62a and the movable portion 62b are aligned in the second direction. The movable portion 62b is movable along the second direction by means of, e.g., an unillustrated air cylinder. The movable portion 62b can take a sandwiching position (see FIG. 4 and FIG. 5) where the yarn Y can be sandwiched with the fixed portion 62a and a release position (see FIG. 1 to FIG. 3 and FIG. 6) which is far from the fixed portion 62a as compared to the sandwiching position. An end portion of the first clamp 62 is provided with a rotational shaft 62c extending along the up-down direction, on the side where the movable portion 62b is provided. The first clamp 62 is rotationally movable by rotating about the rotational shaft 62c. When the movable portion 62b is at the release position, the rotational movement of the first clamp 62 about the rotational shaft 62c is regulated. Meanwhile, when the movable portion 62b is at the sandwiching position, the rotational movement of the first clamp 62 about the rotational shaft 62c is allowed.

[0024] The second clamp 63 is configured to grip each yarn Y threaded to the slit 61a. The second clamp 63 is provided on the other side of the interlacing means 61 in the first direction. The second clamp 63 includes a fixed portion 63a and a movable portion 63b. The fixed portion 63a and the movable portion 63b are aligned in the second direction. The movable portion 63b is movable along the second direction by means of, e.g., an unillustrated air cylinder. The movable portion 63b can take a sandwiching position (see FIG. 4 and FIG. 5) where the yarn Y can be sandwiched with the fixed portion 63a and a release position (see FIG. 1 to FIG. 3 and FIG. 6) which is far from the fixed portion 63a as compared to the sandwiching position. An end portion of the second clamp 63 is provided with a rotational shaft 63c extending along the up-down direction, on the side where the movable portion 63b is provided. The second clamp 63 is rotationally movable by rotating about the rotational shaft 63c. When the movable portion 63b is at the release position, the rotational movement of the second clamp 63 about the rotational shaft 63c is regulated. Meanwhile, when the movable portion 63b is at the sandwiching position, the rotational movement of the second clamp 63 about the rotational shaft 63c is allowed.

[0025] The movement mechanism 90 is configured to move the first clamp 62 and the second clamp 63 so as to elongate and relax the two yarns Y gripped by the both clamps 62 and 63. The movement mechanism 90 may be suitably arranged as long as it is able to move at least one of the first clamp 62 and the second clamp 63 so as to repeatedly elongate and relax the two yarns Y gripped by the first clamp 62 and the second clamp 63. However, when the yarns Y are elongated to the same length by moving only one of the first clamp 62 and the second clamp 63, the one of the clamps 62 and 63 has a long moving distance as compared to the case where both of the first clamp 62 and the second clamp 63 are moved. In this case, the positions of other members need to be adjusted to provide a space required for allowing the one of the clamps 62 and 63 to move. This causes increase in size of the entire device. Therefore, the movement mechanism 90 of the present embodiment is configured to move both of the first clamp 62 and the second clamp 63.

[0026]  The movement mechanism 90 is configured to rotate the first clamp 62 about the rotational shaft 62c, and the second clamp 63 about the rotational shaft 63c. To be more specific, when viewed in the up-down direction, the movement mechanism 90 is able to rotate the first clamp 62 about the rotational shaft 62c both clockwise and counterclockwise (see both solid arrows in FIG. 4). Furthermore, when viewed in the up-down direction, the movement mechanism 90 is able to rotate the second clamp 63 about the rotational shaft 63c both counterclockwise and clockwise (see solid arrows in FIG. 4). In the present embodiment, the movement mechanism 90 is configured to synchronize the rotational movement of the first clamp 62 with the rotational movement of the second clamp 63. To be more specific, when viewed in the up-down direction, the movement mechanism 90 is configured to synchronize the clockwise rotational movement of the first clamp 62 about the rotational shaft 62c with the counterclockwise rotational movement of the second clamp 63 about the rotational shaft 63c. Furthermore, when viewed in the up-down direction, the movement mechanism 90 is configured to synchronize the counterclockwise rotational movement of the first clamp 62 about the rotational shaft 62c with the clockwise rotational movement of the second clamp 63 about the rotational shaft 63c. The movement mechanism 90 is, e.g., a cam mechanism.

[0027] The two guides 66 and 67 are provided for guiding the yarns Y captured by an operator to the interlacing means 61. When viewed in the first direction, both end portions of each of the guides 66 and 67 are provided above a substantially central part of each of the guides 66 and 67 and are inclined downward toward the substantially central part of each of the guides 66 and 67. With this arrangement, at the guides 66 and 67, the yarns Y are guided along the inclined end portions to the substantially central parts. As shown in FIG. 1, the guide 66 is provided on one side of the first clamp 62 in the first direction. The guide 67 is provided on the other side of the second clamp 63 in the first direction.

[0028] The controller 69 is programmed to control the interlacing means 61, the first clamp 62, the second clamp 63, and the movement mechanism 90. To be more specific, the controller 69 is programmed to control the interlacing means 61 so as to inject the compressed air into the slit 61a from an unillustrated nozzle. The controller 69 is programmed to control the first clamp 62 so as to switch the movable portion 62b between the sandwiching position and the release position. The controller 69 is programmed to control the second clamp 63 so as to switch the movable portion 63b between the sandwiching position and the release position. The controller 69 is programmed to control the movement mechanism 90 so as to rotate the first clamp 62 and the second clamp 63 about the respective rotational shafts 62c and 63c. The controller 69 is electrically connected to the interlacing means 61, the first clamp 62, the second clamp 63, and the movement mechanism 90.

(Yarn Joining Operation)

[0029] The following will describe an example of steps of a yarn joining operation that is performed for two yarns Y by the yarn joining device 6, with reference to FIG. 1 to FIG. 6. In the yarn joining operation, the two yarns Y (i.e., yarn Y1 and yarn Y2) are joined together. In the present embodiment, the yarns Y1 and Y2 are high-bulk yarns such as DTYs (i.e., Draw Textured Yarns) which are tightly interlaced. The yarns Y1 and Y2 are not limited to DTYs. The yarns Y1 and Y2 may be yarns interlaced at at least a predetermined density. In this regard, for example, when yarns Y threaded to the slit 61a are interlaced at a predetermined density, the yarns Y are interlaced at least once within the slit 61a in the first direction.

[0030] Before the yarn joining operation, each of (i) the movable portion 62b of the first clamp 62 and (ii) the movable portion 63b of the second clamp 63 is switched to the release position as shown in FIG. 1.

[0031] In the yarn joining operation, to begin with, the operator manually captures one yarn Y, i.e., the yarn Y1.

[0032] Subsequently, while capturing the yarn Y1, the operator performs yarn threading for the guide 67 and the guide 66 in this order. In this regard, as shown in FIG. 2, while being inserted into the slit 61a, the yarn Y1 is threaded between the fixed portion 62a and movable portion 62b of the first clamp 62 and between the fixed portion 63a and movable portion 63b of the second clamp 63.

[0033] After the insertion of the yarn Y1 into the slit 61a is completed, the captured yarn Y1 is released from the operator.

[0034] The operator then manually captures the other yarn Y, i.e., the yarn Y2.

[0035] Subsequently, while capturing the yarn Y2, the operator performs the yarn threading for the guide 66 and the guide 67 in this order. In this regard, as shown in FIG. 3, while being inserted into the slit 61a, the yarn Y2 is threaded between the fixed portion 62a and movable portion 62b of the first clamp 62 and between the fixed portion 63a and movable portion 63b of the second clamp 63.

[0036] After the insertion of the yarn Y2 into the slit 61a is completed, the captured yarn Y2 is released from the operator.

[0037] The controller 69 then executes a yarn gripping control of controlling the first clamp 62 and the second clamp 63 so that the first clamp 62 and the second clamp 63 grip the two yarns Y, i.e., the yarns Y1 and Y2. To be more specific, each of (i) the movable portion 62b of the first clamp 62 and (ii) the movable portion 63b of the second clamp 63 is moved to the sandwiching position by an unillustrated air cylinder as shown in FIG. 4. Because of this, both of the yarns Y1 and Y2 are sandwiched between the fixed portion 62a and movable portion 62b of the first clamp 62 and between the fixed portion 63a and movable portion 63b of the second clamp 63. That is, the yarns Y1 and Y2 are gripped by the first clamp 62 and the second clamp 63. A step of causing the first clamp 62 and the second clamp 63 to grip the two yarns Y (i.e., yarn Y1 and yarn Y2) is equivalent to a yarn gripping step of a yarn joining method of the present invention.

[0038] Subsequently, the controller 69 executes an elongation-relaxation control of controlling the movement mechanism 90 so as to repeatedly elongate and relax the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63. To be more specific, when viewed in the up-down direction, the movement mechanism 90 repeatedly rotates (i) the first clamp 62 about the rotational shaft 62c both clockwise and counterclockwise and (ii) the second clamp 63 about the rotational shaft 63c both counterclockwise and clockwise (see both solid arrows in FIG. 4) . To be precise, when viewed in the up-down direction, the movement mechanism 90 causes the first clamp 62 to rotate clockwise while causing the second clamp 63 to rotate counterclockwise. After that, the movement mechanism 90 causes the first clamp 62 to rotate counterclockwise while causing the second clamp 63 to rotate clockwise. These rotational movements are alternately repeated three times. When viewed in the up-down direction, the clockwise rotational movement of the first clamp 62 about the rotational shaft 62c is synchronized with the counterclockwise rotational movement of the second clamp 63 about the rotational shaft 63c. When viewed in the up-down direction, the counterclockwise rotational movement of the first clamp 62 about the rotational shaft 62c is synchronized with the clockwise rotational direction of the second clamp 63 about the rotational shaft 63c. Because of this, the movement mechanism 90 repeatedly elongates and relaxes the two yarns Y, i.e., the yarns Y1 and Y2 gripped by the first clamp 62 and the second clamp 63. To be more specific, when viewed in the up-down direction, the movement mechanism 90 elongates the yarns Y1 and Y2 by rotating (i) the first clamp 62 about the rotational shaft 62c clockwise and (ii) the second clamp 63 about the rotational shaft 63c counterclockwise. Furthermore, when viewed in the up-down direction, the movement mechanism 90 relaxes the yarns Y1 and Y2 by rotating (i) the first clamp 62 about the rotational shaft 62c counterclockwise and (ii) the second clamp 63 about the rotational shaft 63c clockwise. A step of moving the first clamp 62 and the second clamp 63 by means of the movement mechanism 90 so as to repeatedly elongate and relax the yarns Y1 and Y2 is equivalent to an elongation-relaxation step of the yarn joining method of the present invention.

[0039] The movement mechanism 90 may be suitably arranged, as long as it is able to move the first clamp 62 and the second clamp 63 about the respective rotational shafts 62c and 63c at a movement speed at which each interlaced yarn Y is untwisted. However, when each yarn Y is elongated at a very high speed, each yarn Y may get damaged. Meanwhile, when each yarn Y is elongated at a very low speed, each yarn Y may not be sufficiently untwisted. In consideration of the above, the movement mechanism 90 of the present embodiment is preferably configured to move the first clamp 62 and the second clamp 63 at a movement speed of 10 to 25 mm/s.

[0040] After the elongation-relaxation control, the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63 are relaxed (see FIG. 5).

[0041] Subsequently, while the two yarns Y (i.e., yarn Y1 and yarn Y2) are gripped by the first clamp 62 and the second clamp 63, the controller 69 executes an interlacing control of controlling the interlacing means 61 so as to interlace the two yarns Y (i.e., yarn Y1 and yarn Y2) inserted into the slit 61a. Because of this, the two yarns Y (i.e., yarn Y1 and yarn Y2) are joined together to form one yarn Y. A step of interlacing the two yarns Y (i.e., yarn Y1 and yarn Y2) by means of the interlacing means 61 is equivalent to an interlacing step of the yarn joining method of the present invention. The controller 69 may be configured to release the two yarns Y (i.e., yarn Y1 and yarn Y2) from a grip of the first clamp 62 or a grip of the second clamp 63 at the time when the two yarns Y are interlaced by the interlacing means 61.

[0042] The controller 69 then controls the first clamp 62 and the second clamp 63 so that the first clamp 62 and the second clamp 63 release the two yarns Y, i.e., the yarns Y1 and Y2. To be more specific, each of (i) the movable portion 62b of the first clamp 62 and (ii) the movable portion 63b of the second clamp 63 is moved to the release position by an unillustrated air cylinder as shown in FIG. 6. Because of this, the interlaced yarns Y1 and Y2 are released from the first clamp 62 and the second clamp 63.

[0043] After being interlaced by the interlacing means 61, each of the two yarns Y (i.e., yarn Y1 and yarn Y2) has an interlacing part (interlaced part) and a tail part extending from the interlacing part. To be more specific, in FIG. 6, a tail part of the yarn Y2 is provided on the other side of the slit 61a in the first direction, and a tail part of the yarn Y1 is provided on one side of the slit 61a in the first direction. When a textile or a knitted fabric is made while the tail parts are left, uneven dyeing, etc. disadvantageously occurs. It is therefore necessary to remove the tail parts before the next step starts. The tail parts are therefore cut and removed manually by the operator using, e.g., scissors. By doing this, the yarn joining operation that is performed for the two yarns Y (i.e., yarn Y1 and yarn Y2) by the yarn joining device 6 is completed.

(Effects)

[0044] As described above, the yarn joining device 6 of the present embodiment includes the interlacing means 61, the first clamp 62 and the second clamp 63 which are provided on both sides of the interlacing means 61, the movement mechanism 90, and the controller 69. The controller 69 is programmed to execute the following controls: the elongation-relaxation control of controlling the movement mechanism 90 so as to repeatedly elongate and relax the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63; and, after the elongation-relaxation control, the interlacing control of controlling the interlacing means 61 so as to interlace the two yarns Y (i.e., yarn Y1 and yarn Y2). In the present embodiment, when the two yarns Y (i.e., yarn Y1 and yarn Y2) having been interlaced are joined together, the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63 are repeatedly elongated and relaxed before being interlaced by the interlacing means 61. Because of this, the fibers of each of the two yarns Y (i.e., yarn Y1 and yarn Y2) are loosened between the first clamp 62 and the second clamp 63 so that the two yarns Y (i.e., yarn Y1 and yarn Y2) are untwisted. Subsequently, the interlacing means 61 interlaces the two untwisted yarns Y (i.e., yarn Y1 and yarn Y2) so that the two yarns Y (i.e., yarn Y1 and yarn Y2) are joined together. It is therefore possible to join the two yarns Y (i.e., yarn Y1 and yarn Y2), which have been interlaced, together.

[0045] The movement mechanism 90 of the present embodiment is able to move both of the first clamp 62 and the second clamp 63. In the elongation-relaxation control, the controller 69 is programmed to control the movement mechanism 90 so as to move both of the first clamp 62 and the second clamp 63. When the yarns Y are elongated to the same length by moving only one of the first clamp 62 and the second clamp 63, the one of the clamps 62 and 63 has a long moving distance as compared to the case where both of the first clamp 62 and the second clamp 63 are moved. Therefore, the positions of other members need to be adjusted to provide a space required for allowing the one of the clamps 62 and 63 to move. This causes the increase in size of the entire device. In the present embodiment, the two yarns Y (i.e., yarn Y1 and yarn Y2) are elongated by moving both of the first clamp 62 and the second clamp 63. It is therefore unnecessary to arrange the moving distance of each of the first clamp 62 and the second clamp 63 to be excessively long. This suppresses the increase in size of the device.

[0046] In the present embodiment, the controller 69 is preferably programmed to control the movement mechanism 90 so as to move the first clamp 62 and the second clamp 63 at a movement speed of 10 to 25 mm/s. When each yarn Y is elongated at a very high speed, each yarn Y may get damaged. Meanwhile, when each yarn Y is elongated at a very low speed, each yarn Y may not be sufficiently untwisted. As a result of diligent study, the inventors of the subject application have found that the interlaced yarns Y are efficiently untwisted at the above-described movement speed.

(Modifications)

[0047] The following will describe modifications of the above-described embodiment. The members identical with those in the embodiment above will be denoted by the same reference numerals and the explanations thereof are not repeated.

(First Modification)

[0048] In the embodiment above, when each of the two yarns Y has an interlacing part interlaced by the interlacing means 61 and a tail part extending from the interlacing part, the operator manually cuts each tail part with use of scissors. However, a yarn joining device may include a first clamp cutter (i.e., a first yarn cutting gripping means of the present invention) and a second clamp cutter (i.e., a second yarn cutting gripping means of the present invention) which are provided for cutting the tail parts. The following will describe a yarn joining device 106 including a first clamp cutter 64 and a second clamp cutter 65. The yarn joining device 106 is the same as the yarn joining device of the embodiment above except the first clamp cutter 64 and the second clamp cutter 65, and thus the description thereof will be omitted.

[0049] The first clamp cutter 64 is configured to cut and grip one of two yarns Y threaded to the slit 61a. As shown in FIG. 7, the first clamp cutter 64 is provided on one side of the interlacing means 61 and on the other side of the first clamp 62 in the first direction. In other words, the first clamp cutter 64 is provided between the interlacing means 61 and the first clamp 62 in the first direction. The first clamp cutter 64 includes a fixed blade part 64a, a movable blade part 64b, a fixed gripping part 64c, and a movable gripping part 64d.

[0050] The fixed blade part 64a and the movable blade part 64b are arranged to cut one yarn Y, i.e., the yarn Y1. The fixed blade part 64a and the movable blade part 64b are aligned in the second direction. The fixed blade part 64a and the movable blade part 64b are openable and closeable. To be more specific, the movable blade part 64b is movable along the second direction by means of, e.g., an unillustrated air cylinder. With this arrangement, the fixed blade part 64a and the movable blade part 64b are switched between an open state (see FIG. 7 to FIG. 10 and FIG. 13) and a closed state (see FIG. 11, FIG. 12, and FIG. 14).

[0051] The fixed gripping part 64c and the movable gripping part 64d are arranged to grip one yarn Y, i.e., the yarn Y1. The fixed gripping part 64c and the movable gripping part 64d are aligned in the second direction. The fixed gripping part 64c and the movable gripping part 64d are provided on the other side of the fixed blade part 64a and the movable blade part 64b in the first direction. In other words, the fixed gripping part 64c and the movable gripping part 64d are provided between (i) the interlacing means 61 and (ii) the fixed blade part 64a and the movable blade part 64b in the first direction. The fixed gripping part 64c and the movable gripping part 64d are openable and closeable. To be more specific, the movable gripping part 64d is movable together with the movable blade part 64b. With this arrangement, the fixed gripping part 64c and the movable gripping part 64d are switched between an open state (see FIG. 7 to FIG. 10 and FIG. 13) and a closed state (see FIG. 11, FIG. 12, and FIG. 14).

[0052] The second clamp cutter 65 is configured to cut and grip the other of the two yarns Y threaded to the slit 61a. As shown in FIG. 7, the second clamp cutter 65 is provided on the other side of the interlacing means 61 and on one side of the second clamp 63 in the first direction. In other words, the second clamp cutter 65 is provided between the interlacing means 61 and the second clamp 63 in the first direction. The second clamp cutter 65 includes a fixed blade part 65a, a movable blade part 65b, a fixed gripping part 65c, and a movable gripping part 65d.

[0053] The fixed blade part 65a and the movable blade part 65b are arranged to cut the other yarn Y, i.e., the yarn Y2. The fixed blade part 65a and the movable blade part 65b are aligned in the second direction. The fixed blade part 65a and the movable blade part 65b are openable and closeable. To be more specific, the movable blade part 65b is movable along the second direction by means of, e.g., an unillustrated air cylinder. With this arrangement, the fixed blade part 65a and the movable blade part 65b are switched between an open state (see FIG. 7 to FIG. 10 and FIG. 13) and a closed state (see FIG. 11, FIG. 12, and FIG. 14).

[0054] The fixed gripping part 65c and the movable gripping part 65d are arranged to grip the other yarn Y, i.e., the yarn Y2. The fixed gripping part 65c and the movable gripping part 65d are aligned in the second direction. The fixed gripping part 65c and the movable gripping part 65d are provided on one side of the fixed blade part 65a and the movable blade part 65b in the first direction. In other words, the fixed gripping part 65c and the movable gripping part 65d are provided between (i) the interlacing means 61 and (ii) the fixed blade part 65a and the movable blade part 65b in the first direction. The fixed gripping part 65c and the movable gripping part 65d are openable and closeable. To be more specific, the movable gripping part 65d is movable together with the movable blade part 65b. With this arrangement, the fixed gripping part 65c and the movable gripping part 65d are switched between an open state (see FIG. 7 to FIG. 10 and FIG. 13) and a closed state (see FIG. 11, FIG. 12, and FIG. 14).

[0055] A controller 169 of the first modification is able to control the first clamp cutter 64 and the second clamp cutter 65 in addition to the interlacing means 61, the first clamp 62, the second clamp 63, and the movement mechanism 90.

(Yarn Joining Operation)

[0056] The following will describe an example of steps of a yarn joining operation that is performed for two yarns Y by the yarn joining device 106, with reference to FIG. 7 to FIG. 14. In the yarn joining operation, the two yarns Y (i.e., yarn Y1 and yarn Y2) are joined together. In the first modification, the yarns Y1 and Y2 are high-bulk yarns such as DTYs (i.e., Draw Textured Yarns) which are interlaced at at least a predetermined density. The definition of this predetermined density is the same as in the embodiment above.

[0057] Before the yarn joining operation, each of (i) the movable portion 62b of the first clamp 62 and (ii) the movable portion 63b of the second clamp 63 is switched to the release position as shown in FIG. 7. Furthermore, the first clamp cutter 64 is switched to the open state in which (i) the fixed blade part 64a and the movable blade part 64b and (ii) the fixed gripping part 64c and the movable gripping part 64d are open. In addition to that, the second clamp cutter 65 is switched to the open state in which (i) the fixed blade part 65a and the movable blade part 65b and (ii) the fixed gripping part 65c and the movable gripping part 65d are open.

[0058]  In the yarn joining operation, to begin with, the operator manually captures one yarn Y, i.e., the yarn Y1.

[0059] Subsequently, while capturing the yarn Y1, the operator performs yarn threading for the guide 67 and the guide 66 in this order. In this regard, as shown in FIG. 8, while being inserted into the slit 61a, the yarn Y1 is threaded between the fixed portion 62a and movable portion 62b of the first clamp 62, between the fixed portion 63a and movable portion 63b of the second clamp 63, between the fixed blade part 64a and movable blade part 64b of the first clamp cutter 64, and between the fixed gripping part 64c and movable gripping part 64d of the first cramp cutter 64. At this time, the yarn Y1 is not threaded between the fixed blade part 65a and movable blade part 65b of the second clamp cutter 65 and between the fixed gripping part 65c and movable gripping part 65d of the second clamp cutter 65. To be more specific, the yarn Y1 passes outside the movable blade part 65b and movable gripping part 65d of the second clamp cutter 65 in the second direction.

[0060] After the insertion of the yarn Y1 into the slit 61a is completed, the captured yarn Y1 is released from the operator.

[0061]  The operator then manually captures the other yarn Y, i.e., the yarn Y2.

[0062] Subsequently, while capturing the yarn Y2, the operator performs the yarn threading for the guide 66 and the guide 67 in this order. In this regard, as shown in FIG. 9, while being inserted into the slit 61a, the yarn Y2 is threaded between the fixed portion 62a and movable portion 62b of the first clamp 62, between the fixed portion 63a and movable portion 63b of the second clamp 63, between the fixed blade part 65a and movable blade part 65b of the second clamp cutter 65, and between the fixed gripping part 65c and movable gripping part 65d of the second cramp cutter 65. At this time, the yarn Y2 is not threaded between the fixed blade part 64a and movable blade part 64b of the first clamp cutter 64 and between the fixed gripping part 64c and movable gripping part 64d of the first clamp cutter 64. To be more specific, the yarn Y2 passes outside the movable blade part 64b and movable gripping part 64d of the first clamp cutter 64 in the second direction.

[0063] After the insertion of the yarn Y2 into the slit 61a is completed, the captured yarn Y2 is released from the operator.

[0064]  The controller 169 then executes the yarn gripping control of controlling the first clamp 62 and the second clamp 63 so that the first clamp 62 and the second clamp 63 grip the two yarns Y (i.e., yarns Y1 and Y2). To be more specific, each of (i) the movable portion 62b of the first clamp 62 and (ii) the movable portion 63b of the second clamp 63 is moved to the sandwiching position by an unillustrated air cylinder as shown in FIG. 10. Because of this, both of the two yarns Y (i.e., yarn Y1 and yarn Y2) are sandwiched between the fixed portion 62a and movable portion 62b of the first clamp 62 and between the fixed portion 63a and movable portion 63b of the second clamp 63. That is, the two yarns Y (i.e., yarn Y1 and yarn Y2) are gripped by the first clamp 62 and the second clamp 63. A step of causing the first clamp 62 and the second clamp 63 to grip the two yarns Y (i.e., yarns Y1 and Y2) is equivalent to the yarn gripping step of the yarn joining method of the present invention.

[0065] Subsequently, the controller 169 executes the elongation-relaxation control of controlling the movement mechanism 90 so as to repeatedly elongate and relax the two yarns Y (i.e., yarns Y1 and Y2) gripped by the first clamp 62 and the second clamp 63. To be more specific, when viewed in the up-down direction, the movement mechanism 90 repeatedly rotates (i) the first clamp 62 about the rotational shaft 62c both clockwise and counterclockwise and (ii) the second clamp 63 about the rotational shaft 63c both counterclockwise and clockwise (see both solid arrows in FIG. 10). To be precise, when viewed in the up-down direction, the movement mechanism 90 causes the first clamp 62 to rotate clockwise while causing the second clamp 63 to rotate counterclockwise. After that, the movement mechanism 90 causes the first clamp 62 to rotate counterclockwise while causing the second clamp 63 to rotate clockwise. These rotational movements are alternately repeated three times. When viewed in the up-down direction, the clockwise rotational movement of the first clamp 62 about the rotational shaft 62c is synchronized with the counterclockwise rotational movement of the second clamp 63 about the rotational shaft 63c. When viewed in the up-down direction, the counterclockwise rotational movement of the first clamp 62 about the rotational shaft 62c is synchronized with the clockwise rotational movement of the second clamp 63 about the rotational shaft 63c. Because of this, the movement mechanism 90 repeatedly elongates and relaxes the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63. To be more specific, when viewed in the up-down direction, the movement mechanism 90 elongates the two yarns Y (i.e., yarn Y1 and yarn Y2) by rotating (i) the first clamp 62 about the rotational shaft 62c clockwise and (ii) the second clamp 63 about the rotational shaft 63c counterclockwise. Furthermore, when viewed in the up-down direction, the movement mechanism 90 relaxes the two yarns Y (i.e., yarn Y1 and yarn Y2) by rotating (i) the first clamp 62 about the rotational shaft 62c counterclockwise and (ii) the second clamp 63 about the rotational shaft 63c clockwise. A step of moving the first clamp 62 and the second clamp 63 by means of the movement mechanism 90 so as to repeatedly elongate and relax the two yarns Y (i.e., yarn Y1 and yarn Y2) is equivalent to the elongation-relaxation step of the yarn joining method of the present invention.

[0066] As in the embodiment above, the movement mechanism 90 is preferably configured to move the first clamp 62 and the second clamp 63 about the respective rotational shafts 62c and 63c at a movement speed of 10 to 25 mm/s.

[0067] The controller 169 then executes a yarn cutting-gripping control of controlling the first clamp cutter 64 and the second clamp cutter 65 so that first clamp cutter 64 cuts and grips the yarn Y1 and the second clamp cutter 65 cuts and grips the yarn Y2. To be more specific, as shown in FIG. 11, the movable blade part 64b and the movable gripping part 64d are moved by an unillustrated air cylinder so that the first clamp cutter 64 is switched to the closed state in which (i) the fixed blade part 64a and the movable blade part 64b and (ii) the fixed gripping part 64c and the movable gripping part 64d are closed. Because of this, the yarn Y1 is cut by the fixed blade part 64a and movable blade part 64b of the first clamp cutter 64. A part of the yarn Y1 is provided on the other side of a cut part of the yarn Y1 in the first direction, and this part of the yarn Y1 on the other side in the first direction is gripped by the fixed gripping part 64c and the movable gripping part 64d. At the same time, the movable blade part 65b and the movable gripping part 65d are moved by an unillustrated air cylinder so that the second clamp cutter 65 is switched to the closed state in which (i) the fixed blade part 65a and the movable blade part 65b and (ii) the fixed gripping part 65c and the movable gripping part 65d are closed. Because of this, the yarn Y2 is cut by the fixed blade part 65a and movable blade part 65b of the second clamp cutter 65. A part of the yarn Y2 is provided on one side of a cut part of the yarn Y2 in the first direction, and this part of the yarn Y2 on one side in the first direction is gripped by the fixed gripping part 65c and the movable gripping part 65d. A step of causing the first clamp cutter 64 to cut and grip the yarn Y1 and the second clamp cutter 65 to cut and grip the yarn Y2 is equivalent to a yarn cutting-gripping step of the yarn joining method of the present invention.

[0068] In the first modification, the timing for the controller 169 to execute the yarn cutting-gripping control and the timing for the controller 169 to execute the elongation-relaxation control are not limited. In other words, in the first modification, the following timings are not limited: the timing for the first clamp cutter 64 to cut and grip the yarn Y1; the timing for the second clamp cutter 65 to cut and grip the yarn Y2; and the timing to repeatedly elongate and relax the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63. The first modification may be suitably arranged as long as the two interlaced yarns Y can be untwisted. For example, in the movement mechanism 90, the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63 may be repeatedly elongated and relaxed by moving the first clamp 62 and the second clamp 63 after the first clamp cutter 64 cuts and grips the yarn Y1 and the second clamp cutter 65 cuts and grips the yarn Y2. However, when the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63 are repeatedly elongated and relaxed after the first clamp cutter 64 cuts and grips the yarn Y1 and the second clamp cutter 65 cuts and grips the yarn Y2, the two interlaced yarns Y (i.e., yarn Y1 and yarn Y2) may be unevenly untwisted or may not be sufficiently untwisted. The reasons of occurrence of these problems will be described later in detail, along with the effects of the first modification. In the first modification, the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63 are repeatedly elongated and relaxed before the first clamp cutter 64 cuts and grips the yarn Y1 and the second clamp cutter 65 cuts and grips the yarn Y2. This arrangement is preferable to solve these problems.

[0069] Subsequently, as shown in FIG. 12, when viewed in the up-down direction, the movement mechanism 90 rotates (i) the first clamp 62 about the rotational shaft 62c clockwise once and (ii) the second clamp 63 about the rotational shaft 63c counterclockwise once (see full-line arrows in FIG. 12). Because of this, the yarn Y2 gripped by the first clamp 62 and the second clamp cutter 65 and the yarn Y1 gripped by the second clamp 63 and the first clamp cutter 64 are elongated in the first direction.

[0070] The controller 169 then controls the first clamp cutter 64 and the second clamp cutter 65 so that the first clamp cutter 64 releases the yarn Y1 and the second clamp cutter 65 releases the yarn Y2. To be more specific, as shown in FIG. 13, the movable blade part 64b and the movable gripping part 64d are moved by an unillustrated air cylinder so that the first clamp cutter 64 is switched to the open state in which (i) the fixed blade part 64a and the movable blade part 64b and (ii) the fixed gripping part 64c and the movable gripping part 64d are open. Because of this, the yarn Y1, i.e., a grip by the first clamp cutter 64 is released. At this time, the yarn Y2 gripped by the first clamp 62 is pushed and curved in the second direction by the moving movable blade part 64b and the moving movable gripping part 64d. Meanwhile, the movable blade part 65b and the movable gripping part 65d are moved by an unillustrated air cylinder so that the second clamp cutter 65 is switched to the open state in which (i) the fixed blade part 65a and the movable blade part 65b and (ii) the fixed gripping part 65c and the movable gripping part 65d are open. Because of this, the yarn Y2, i.e., a grip by the second clamp cutter 65 is released. At this time, the yarn Y1 gripped by the second clamp 63 is pushed and curved in the second direction by the moving movable blade part 65b and the moving movable gripping part 65d. The switch of the first clamp cutter 64 from the closed state to the open state is performed substantially at the same time as the switch of the second clamp cutter 65 from the closed state to the open state in a synchronous manner.

[0071] Subsequently, the controller 169 executes the interlacing control of controlling the interlacing means 61 so as to interlace the two yarns Y (i.e., yarn Y1 and yarn Y2) inserted into the slit 61a. To be more specific, the two yarns Y (i.e., yarn Y1 and yarn Y2) threaded to the slit 61a start to be interlaced by the interlacing means 61 substantially at the same time as the yarn Y1 gripped by the first clamp cutter 64 and the yarn Y2 gripped by the second clamp cutter 65 are released as described above. To be precise, the length of time from when the first clamp cutter 64 releases the yarn Y1 and the second clamp cutter 65 releases the yarn Y2 to when the interlacing means 61 interlaces the two yarns Y (i.e., yarn Y1 and yarn Y2) is, e.g., 0.05 to 1.00 second. Because of this, the two yarns Y (i.e., yarn Y1 and yarn Y2) are joined together to form one yarn Y. A step of interlacing the two yarns Y (i.e., yarn Y1 and yarn Y2) by means of the interlacing means 61 is equivalent to the interlacing step of the yarn joining method of the present invention.

[0072] To be more specific, as shown in FIG. 14, when the two yarns Y (i.e., yarn Y1 and yarn Y2) threaded to the slit 61a are being interlaced by the interlacing means 61, the movable blade part 64b and the movable gripping part 64d are moved by an unillustrated air cylinder so that the first clamp cutter 64 is switched to the closed state in which (i) the fixed blade part 64a and the movable blade part 64b and (ii) the fixed gripping part 64c and the movable gripping part 64d are closed. Because of this, the yarn Y2 pushed and curved in the second direction by the first clamp cutter 64 is released from being curved. Meanwhile, the movable blade part 65b and the movable gripping part 65d are moved by an unillustrated air cylinder so that the second clamp cutter 65 is switched to the closed state in which (i) the fixed blade part 65a and the movable blade part 65b and (ii) the fixed gripping part 65c and the movable gripping part 65d are closed. Because of this, the yarn Y1 pushed and curved in the second direction by the second clamp cutter 65 is released from being curved. The switch of the first clamp cutter 64 from the open state to the closed state is performed substantially at the same time as the switch of the second clamp cutter 65 from the open state to the closed state in a synchronous manner. The switch of each of the first clamp cutter 64 and the second clamp cutter 65 from the open state to the closed state may be performed after the interlacing control by the interlacing means 61 ends.

[0073] Finally, each of the movable portions 62b and 63b is moved to the release position by an unillustrated air cylinder. Because of this, a single yarn formed by joining the two yarns Y (i.e., yarn Y1 and yarn Y2) together is released from the grip by the first clamp 62 and the second clamp 63. As such, the yarn joining operation that is performed for the two yarns Y (i.e., yarn Y1 and yarn Y2) by the yarn joining device 6 is completed.

(Effects)

[0074] The following will describe the effects of the first modification. The yarn joining device 106 of the first modification includes the interlacing means 61, the first clamp 62 and the second clamp 63 which are provided so as to sandwich the interlacing means 61, the movement mechanism 90, and the controller 169. The controller 169 is programmed to execute the following controls: the elongation-relaxation control of controlling the movement mechanism 90 so as to repeatedly elongate and relax the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63; and, after the elongation-relaxation control, the interlacing control of controlling the interlacing means 61 so as to interlace the two yarns Y (i.e., yarn Y1 and yarn Y2). In the first modification, when the two yarns Y (i.e., yarn Y1 and yarn Y2) having been interlaced are joined together, the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63 are repeatedly elongated and relaxed before being interlaced by the interlacing means 61. Because of this, the fibers of each of the two yarns Y (i.e., yarn Y1 and yarn Y2) are loosened between the first clamp 62 and the second clamp 63 so that the two yarns Y (i.e., yarn Y1 and yarn Y2) are untwisted. Subsequently, the interlacing means 61 interlaces the two untwisted yarns Y (i.e., yarn Y1 and yarn Y2) so that the two yarns Y (i.e., yarn Y1 and yarn Y2) are joined together. It is therefore possible to join the two yarns Y (i.e., yarn Y1 and yarn Y2), which have been interlaced, together.

[0075] The yarn joining device 106 of the first modification further includes the first clamp cutter 64 which is provided between the interlacing means 61 and the first clamp 62 and which is configured to cut and grip the yarn Y1, and the second clamp cutter 65 which is provided between the interlacing means 61 and the second clamp 63 and which is configured to cut and grip the yarn Y2. The controller 169 is programed to execute, before the interlacing control, the yarn cutting-gripping control of controlling the first clamp cutter 64 and the second clamp cutter 65 so that first clamp cutter 64 cuts and grips the yarn Y1 and the second clamp cutter 65 cuts and grips the yarn Y2.

[0076]  Assume that each of the two yarns Y has an interlacing part (interlaced part) and a part extending from the interlacing part. In this case, the part extending from the interlacing part is referred to as a tail part. Such tail parts of the yarns Y cause, e.g., uneven dyeing in a textile or a knitted fabric. It is therefore necessary to remove the tail parts before the next step starts. In the first modification, the first clamp cutter 64 is provided between the interlacing means 61 and the first clamp 62, and the second clamp cutter 65 is provided between the interlacing means 61 and the second clamp 63. With this arrangement, before the two yarns Y (i.e., yarn Y1 and yarn Y2) are interlaced by the interlacing means 61, the tail parts of the yarns Y1 and Y2 are arranged to be short not by hand.

[0077] The controller 169 is programmed to execute the yarn cutting-gripping control after the elongation-relaxation control. In the yarn joining device 106, when one yarn Y, i.e., the yarn Y1 is cut and gripped by the first clamp cutter 64, one yarn Y1 is griped by the first clamp cutter 64 and the second clamp 63. Similarly, when the other yarn Y, i.e., the yarn Y2 is cut and gripped by the second clamp cutter 65, the other yarn Y2 is griped by the second clamp cutter 65 and the first clamp 62. In this regard, the two yarns Y (i.e., yarn Y1 and yarn Y2) may be repeatedly elongated and relaxed after one yarn Y1 is cut and gripped by the first clamp cutter 64 and the other yarn Y2 is cut and gripped by the second clamp cutter 65. In other words, instead of the first clamp 62 and the second clamp 63, (i) the first clamp cutter 64 and the second clamp 63 may elongate and relax one yarn Y1 and (ii) the second clamp cutter 65 and the first clamp 62 may elongate and relax the other yarn Y2. In this case, one yarn Y1 is elongated and relaxed only by the movement of the second clamp 63, and the other yarn Y2 is elongated and relaxed only by the movement of the first clamp 62. Because of this, one yarn Y1 is untwisted in the vicinity of the second clamp 63, and the other yarn Y2 is untwisted in the vicinity of the first clamp 62. Therefore, the two yarns Y (i.e., yarn Y1 and yarn Y2) are unevenly untwisted. As a result, even if the interlacing means 61 interlaces the two unevenly-untwisted yarns Y (i.e., yarn Y1 and yarn Y2), the yarns Y may not be properly joined together. Furthermore, one yarn Y1 is not sufficiently untwisted at a part gripped by the first clamp cutter 64, and the other yarn Y2 is not sufficiently untwisted at a part gripped by the second clamp cutter 65. This is because each yarn Y is fixed by a corresponding clamp cutter. As a result, even if the interlacing means 61 interlaces the two insufficiently-untwisted yarns Y (i.e., yarn Y1 and yarn Y2), the yarns Y may not be properly joined together. In the first modification, before being cut and gripped by the first clamp cutter 64 and the second clamp cutter 65, the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63 are repeatedly elongated and relaxed. Because of this, the two yarns Y (i.e., yarn Y1 and yarn Y2) are elongated and relaxed while being gripped by the first clamp 62 and the second clamp 63. The two yarns Y (i.e., yarn Y1 and yarn Y2) are therefore evenly untwisted. The two yarns Y (i.e., yarn Y1 and yarn Y2) are cut and gripped by the respective clamp cutters after being untwisted. Because of this, the two yarns Y (i.e., yarn Y1 and yarn Y2) are sufficiently untwisted at parts gripped by the respective clamp cutters. As a result, when the two yarns Y (i.e., yarn Y1 and yarn Y2) are interlaced by the interlacing means 61, the yarns Y are further reliably joined together.

(Other Modifications)

[0078] In the embodiment above, the elongation and relaxation of the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63 are alternately repeated by moving the first clamp 62 and the second clamp 63. However, when the two yarns Y (i.e., yarn Y1 and yarn Y2) gripped by the first clamp 62 and the second clamp 63 are repeatedly elongated and relaxed by moving the first clamp 62 and the second clamp 63, the number of times of each of this elongation and this relaxation may be two or may be four or more.

[0079] In the embodiment above, the single movement mechanism 90 is shared between the first clamp 62 and the second clamp 63. However, a movement mechanism configured to move the first clamp 62 and a movement mechanism configured to move the second clamp 63 may be independently provided.

[0080] In the embodiment above, the first clamp 62 is configured to rotate about the rotational shaft 62c, and the second clamp 63 is configured to rotate about the rotational shaft 63c. However, the way each clamp moves is not limited to a rotational movement. For example, the first clamp 62 and the second clamp 63 may be configured to elongate and relax the yarn Y1 and the yarn Y2 by moving linearly along, e.g., rails extending in a base longitudinal direction.

Claims

1. A yarn joining device (6) comprising: an interlacing means (61) configured to interlace and join two yarns (Y) together;

a first yarn gripping means (62) and a second yarn gripping means (63) which are able to grip the yarns (Y) and which are provided on both sides of the interlacing means (61) ;

a movement mechanism (90) which is able to move at least one of the first yarn gripping means (62) and the second yarn gripping means (63); and

a controlling means (69) programmed to control the interlacing means (61), the first yarn gripping means (62), the second yarn gripping means (63), and the movement mechanism (90), and

the controlling means (69) being programmed to execute:

a yarn gripping control of controlling the first yarn gripping means (62) and the second yarn gripping means (63) so that the first yarn gripping means (62) and the second yarn gripping means (63) grip the two yarns (Y);

an elongation-relaxation control of controlling, after the yarn gripping control, the movement mechanism (90) so as to repeatedly elongate and relax the two yarns (Y) gripped by the first yarn gripping means (62) and the second yarn gripping means (63); and

an interlacing control of controlling, after the elongation-relaxation control, the interlacing means (61) so as to interlace the two yarns (Y).

2. The yarn joining device (6) according to claim 1, further comprising: a first yarn cutting gripping means (64) which is provided between the interlacing means (61) and the first yarn gripping means (62) and which is configured to cut and grip one of the yarns (Y); and

a second yarn cutting gripping means (65) which is provided between the interlacing means (61) and the second yarn gripping means (63) and which is configured to cut and grip the other of the yarns (Y), wherein,

the controlling means (69) is able to control the first yarn cutting gripping means (64) and the second yarn cutting gripping means (65) and

is programmed to execute, before the interlacing control, a yarn cutting-gripping control of controlling the first yarn cutting gripping means (64) and the second yarn cutting gripping means (65) so that the first yarn cutting gripping means (64) cuts and grips one yarn (Y) among the two yarns (Y) and the second yarn cutting gripping means (65) cuts and grips the other yarn (Y) among the two yarns (Y) .

3. The yarn joining device (6) according to claim 2, wherein, the controlling means (69) is programmed to execute the yarn cutting-gripping control after the elongation-relaxation control.

4. The yarn joining device (6) according to any one of claims 1 to 3, wherein, the movement mechanism (90) is able to move both of the first yarn gripping means (62) and the second yarn gripping means (63), and
in the elongation-relaxation control, the controlling means (69) is programmed to control the movement mechanism (90) so as to move the both of the first yarn gripping means (62) and the second yarn gripping means (63).

5. The yarn joining device (6) according to any one of claims 1 to 4, wherein, in the elongation-relaxation control, the controlling means (69) is programmed to control the movement mechanism (90) so as to move the at least one of the first yarn gripping means (62) and the second yarn gripping means (63) at a movement speed of 10 to 25 mm/s.

6. A yarn joining method of joining two interlaced yarns (Y) together by means of a yarn joining device (6) including: an interlacing means (61) configured to interlace and join the two yarns (Y) together; and a first yarn gripping means (62) and a second yarn gripping means (63) which are able to grip the yarns (Y) and which are provided on both sides of the interlacing means (61), the yarn joining method comprising:

a yarn gripping step of causing the first yarn gripping means (62) and the second yarn gripping means (63) to grip the two yarns (Y);

after the yarn gripping step, an elongation-relaxation step of moving at least one of the first yarn gripping means (62) and the second yarn gripping means (63) so as to repeatedly elongate and relax the two yarns (Y) gripped by the first yarn gripping means (62) and the second yarn gripping means (63); and

an interlacing step of interlacing the two yarns (Y) by means of the interlacing means (61) after the elongation-relaxation step.

7. The yarn joining method according to claim 6 for joining the two interlaced yarns (Y) together by means of the yarn joining device (6) further including: a first yarn cutting gripping means (64) which is provided between the interlacing means (61) and the first yarn gripping means (62) and which is configured to cut and grip one of the yarns (Y); and a second yarn cutting gripping means (65) which is provided between the interlacing means (61) and the second yarn gripping means (63) and which is configured to cut and grip the other of the yarns (Y), further including
a yarn cutting-gripping step of causing, before the interlacing step, the first yarn cutting gripping means (64) to cut and grip one yarn (Y) among the two yarns (Y) and the second yarn cutting gripping means (65) to cut and grip the other yarn (Y) among the two yarns (Y).

8. The yarn joining method according to claim 7, wherein, the yarn cutting-gripping step is executed after the elongation-relaxation step.

Drawing