JP4276551B2 - Multi-head sewing machine - Google Patents

Description

  The present invention relates to a multi-head sewing machine provided with a plurality of sewing heads capable of sewing a string-like member such as a tape or a cord onto a cloth by main sewing. In particular, when a multi-head sewing machine is used so that only a part of the plurality of sewing heads are operated and the remaining sewing heads are stopped, the sewing thread comes off from the needle holes of the sewing needles in the operating heads that are not operating. The present invention relates to a multi-head sewing machine that can prevent this from occurring with a simple configuration.

  Conventionally, a needle bar that includes a sewing needle at the lower end and is driven up and down, a balance that is swung in synchronization with the vertical drive of the needle bar, and a shaft that is assembled coaxially with the needle bar. A rotating body that can freely rotate around the center, and a guide that rotates together with the rotating body and guides the string-like member to the needle base position of the sewing needle, according to the movement direction of the fabric based on predetermined embroidery data The rotator is rotationally controlled and the direction of the guide is changed so that the guide direction of the string-like member to the needle base of the sewing needle is appropriate, and the string-like member is sewn to the fabric by the main sewing. A multi-head sewing machine having a plurality of sewing heads that can be used is known. As a multi-head sewing machine having a plurality of sewing heads capable of sewing such a string-like member, a sewing machine having only a plurality of sewing heads capable of sewing a string-like member or a sewing machine capable of sewing a string-like member. Various multi-head sewing machines are known, such as a sewing machine having a head and an embroidery sewing head capable of normal embroidery alternately.

  By the way, in the type of multi-head sewing machine described above, there are cases where only a part of the plurality of sewing heads are operated and the remaining sewing heads are not operated but are stopped. Each sewing head of the multi-head sewing machine is provided with a common sewing machine spindle, and the needle bar of each sewing machine head is moved up and down by the rotation of the sewing machine spindle so that the string-like member is sewn on the fabric. Yes. Therefore, in order to stop the operation of a part of the sewing head as described above, the transmission of the rotational drive of the sewing machine spindle to the needle bar is interrupted by a known jump mechanism, and the needle bar moves up and down in accordance with the rotation of the sewing machine spindle. It is necessary to have a “jump state” that does not move. In the sewing head that stops operation in this way, it is preferable to also stop the operation of the balance at the same time. In particular, in a sewing head that can sew a string-like member, if the balance is swung while the operation is suspended, the thread passed through the needle hole of the sewing needle is pulled by the balance and comes out of the needle hole. This is because it can happen. This is because the holding member for holding the thread end of the sewing thread provided behind the sewing needle in the embroidery sewing head is not arranged in the sewing head capable of sewing the string-like member. That is, since the sewing head capable of sewing the string-like member has a rotating body that rotates around the axis of the needle bar, a holding member that holds the thread end of the sewing thread is provided behind the sewing needle. The thread end of the sewing thread is not held. For this reason, the sewing thread passed through the needle hole of the sewing needle is pulled by the swinging balance and comes out of the needle hole.

In order to solve the above-described problems, a sewing machine configured to be able to stop the swing of the balance of the sewing head while the sewing head that can sew the string-like member is stopped is disclosed in Patent Document 1 shown below. Is disclosed. According to the multi-head sewing machine described in Patent Document 1, the boss portion of the balance is attached to the sewing machine arm so that the balance shaft arranged in parallel with the main spindle of the sewing machine can rotate around the axis and slide along the axis. It is supported. In this case, the balance is repeatedly swung around the axis of the balance shaft by a balance drive arm that is interlocked with the rotation of the balance cam fixed to the main spindle of the sewing machine. A spring is provided on the shaft of the balance shaft, and is always biased so that the mutual gears of the boss portion of the balance and the balance drive arm are engaged with each other, so that the balance drive arm moves to the balance. Power transmission is performed. A push pin for sliding the balance is slidably supported on the sewing machine arm. When the push pin is manually slid, the push pin comes into contact with the balance and the balance is slid together. When the balance is slid, the gears of the boss portion of the balance and the balance driving arm are disengaged from each other, power transmission from the balance driving arm to the balance is cut off, and the balance is stopped. At this time, the balance is held in a predetermined swinging posture with respect to the balance shaft, and the push pin is held in a slid state. In this way, when the operation of the sewing head is stopped, the push pin is operated to stop the balance so that the sewing thread passed through the needle hole of the sewing needle is not pulled out.
JP-A-8-299639

As described above, in the prior art as described above, the balance is secured so that the thread passed through the needle hole of the sewing needle is not pulled out during the suspension of the operation of the sewing head capable of sewing the string-like member. The oscillation of the motor is also stopped. Thus, in order to stop the swinging of the balance, a blocking mechanism for cutting off power transmission from the main spindle of the sewing machine to the balance is required, such as a slidably supported balance or a push pin for sliding the balance. However, if such a shut-off mechanism is provided, not only the structure of the sewing machine head is complicated, but also the problem that the assembly to the sewing machine is complicated and the cost is increased is inconvenient. there were.
Further, in the multi-head sewing machine described in Patent Document 1, the operation of the push pin for pausing the balance is manually performed. When pausing a plurality of sewing machine heads, It is necessary to operate the push pins, which is not only laborious but also forgetting the operation. However, in order to be able to automatically operate the push pin of each sewing head, an actuator for sliding the push pin is required for each sewing head, and installation of such an actuator is costly. There was a problem.

  The present invention has been made in view of the above points, and by holding the sewing thread while the sewing head that can sew the string-like member with a simple configuration is suspended, it is not necessary to pause the driving of the balance. An object of the present invention is to provide a multi-head sewing machine in which a thread passed through a needle hole of a sewing needle is prevented from coming off.

A sewing machine according to the present invention of claim 1 includes a needle bar that is driven up and down together with a sewing needle attached to a lower end portion, and a balance that is swung in synchronization with the vertical drive of the needle bar. A holding member for holding a sewing thread stretched over the balance at a position downstream from the balance and upstream from a sewing needle of the needle bar, and the needle when the sewing machine head is in operation A cloth presser body that is driven up and down in synchronization with the vertical movement of the bar and that is retreated to the upper retreat position when the sewing head is suspended is provided on the sewing head, and the holding member is a yarn Can be selectively displaced to either the first position that does not hold the yarn or the second position that holds the yarn, and the holding member is moved in conjunction with the movement of the cloth presser to the retracted position. The interlocking mechanism positioned at the second position is the sewing machine. Further provided in head, wherein when the movement of the needle bar and then stopped to pause the operation of the machine heads, the presser foot is located at the second position in conjunction with the movement of moving to the retracted position By holding the sewing thread by the holding member, the movement of the sewing thread downstream of the balance is stopped regardless of the movement of the balance.
The multi-head sewing machine according to the present invention of claim 5 is a needle bar that is driven up and down together with a sewing needle attached to a lower end, a balance that is swung in synchronization with the vertical drive of the needle bar, and the needle bar A rotating body that is assembled on the same axis and freely rotatable around its axis, and a guide that rotates together with the rotating body and guides the string-like member to the needle base position of the sewing needle. The string member is controlled while controlling the rotation of the rotating body according to the movement direction of the fabric based on the data and changing the guide direction so that the guide direction of the string member to the needle base of the sewing needle is appropriate. A multi-head sewing machine having a plurality of sewing heads that can be sewn onto a fabric by main sewing, a holding member for holding the sewing thread stretched over the balance downstream from the balance, and the needle bar when the sewing head is in operation Driven up and down in synchronization with the vertical movement of On the other hand, when the sewing machine head is not in operation, the presser foot is retracted to the upper retracted position and is not driven up and down, and is stretched over the balance as the presser foot is retracted. An interlocking mechanism for interlocking the holding member so as to hold the sewing thread is provided in the sewing machine head, and in the sewing machine head that stops operation, the holding member is interlocked with the movement of the cloth presser body to the retracted position. The movement of the sewing thread downstream of the balance is stopped by holding the sewing thread.

  According to this, a holding member for holding the sewing thread is provided downstream of the swinging balance, and the sewing thread is held by the holding member while the sewing head is capable of sewing the string-like member. Regardless of the swinging of the balance, the movement of the sewing thread downstream of the balance is stopped. That is, while the sewing machine head is suspended, the needle bar driven up and down together with the sewing needle attached to the lower end can be prevented from being driven up and down, but the balance is swung. . The leading end of the sewing thread stretched over the balance is passed through the needle hole of the sewing needle attached to the needle bar. When the balance swings, the thread that is being stretched is pulled or loosened in response to the swing, but the sewing machine head that is not in operation is held downstream of the balance by the holding member, that is, at a position close to the sewing needle. Since the sewing thread is held, the sewing thread passed through the needle hole does not come out of the needle hole regardless of the operation of the balance. As described above, according to the present invention, the sewing thread can be formed in the needle hole even when the sewing head is provided with a holding member for holding the sewing thread downstream of the balance without stopping the operation of the balance during the suspension of the operation of the sewing head. It is possible to prevent you from getting out of it. Therefore, a dedicated shut-off device for stopping the operation of the balance is not required, a multi-head sewing machine with a simple structure of the sewing head can be provided, and the cost of the multi-head sewing machine can be suppressed.

Furthermore, according to the present invention, when the sewing head is stopped , the sewing thread is held by the holding member in conjunction with the retraction of the presser foot to the retreat position. Is not necessary. Further, since the holding member is automatically driven with the retracting operation of the presser foot, the sewing thread is held even if the operator does not bother to drive the holding member.

According to the present invention, a dedicated shut-off device for stopping the operation of the balance is not required, and the structure of the sewing head is simplified. In addition, since the holding member is provided at a position downstream from the balance and upstream from the sewing needle of the needle bar, even if there is a rotating body around the sewing needle, it does not get in the way. A simple sewing thread holding structure suitable for a sewing machine head can be provided. Further, if the present invention is applied to a sewing head that can sew a string-like member, the holding member that holds the sewing thread can be used to hold the sewing thread at a position downstream of the balance with the holding member while the sewing head is not operating. Since the sewing thread does not come out of the needle hole even if the balance operation is not paused, there is no need for a shut-off device to pause the balance, and the structure of the sewing head is simplified. There is an excellent effect that the cost can be suppressed.
Further, since the holding operation of the sewing thread by the holding member is performed in conjunction with the retracting operation of the presser foot to the retracted position when the sewing machine head is stopped, a separate actuator for driving the holding member is provided. There is no need, and it is possible to prevent the operator from forgetting to operate, which may occur when the operator manually operates the holding member.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

  First, the outline of the multi-head sewing machine according to the present invention will be briefly described. FIG. 1 is a front external view showing an embodiment of a multi-head sewing machine according to the present invention. In this embodiment, a multi-head sewing machine having a plurality (eight here) of sewing heads H capable of sewing a string-like member is shown. In FIG. 1, the front side corresponds to the front surface of a multi-head sewing machine on which an operator who performs a sewing operation or the like is actually located.

  In the multi-head sewing machine shown in FIG. 1, an upper frame 2 is disposed above a long sewing table 1 extending in the horizontal direction (X direction in the drawing), and the upper frame 2 is disposed on the front surface of the upper frame 2. Sewing heads H are arranged at equal intervals along the longitudinal direction 2 (the X direction in the drawing). Below each sewing head H, a hook base 4 that supports the hook 3 is provided at substantially the same height as the sewing machine table 1 corresponding to each sewing head H. Further, a sewing frame 5 for expanding and holding the sewing product is placed on the upper surface of the sewing machine table 1, and the sewing frame 5 is driven in the front-rear and left-right directions by a driving mechanism (not shown) disposed below the table. Is done. Each sewing head H is provided with a common sewing machine main shaft 6 extending therethrough, and the sewing needle of the sewing head H is reciprocated up and down by the rotation of the sewing machine main shaft 6. By the cooperation of the sewing needle and the hook 3 rotated on the hook base 4, sewing is performed on the sewing object stretched and held on the sewing frame 5.

  Next, details of the sewing head H in the multi-head sewing machine shown in FIG. 1 will be described. 2 is a front view of the sewing head H arranged in the multi-head sewing machine shown in FIG. 1, FIG. 3 is a left side view of the sewing head H, FIG. 4 is a left side sectional view of the sewing head H, and FIG. It is the side view which fractured and expressed a part of H. The sewing head H shown in FIGS. 2 to 5 shows a case where the presser foot 28 is in the sewing position. Hereinafter, the structure and operation of the sewing head H will be described with reference to FIGS. As shown in these drawings, the sewing machine main shaft 6 passes through the sewing machine arm 7, and the left side surface of the sewing machine arm 7 has a motor 22 for jump control of the needle bar 8 and a presser foot support 27. A motor 41 for driving up and down and a motor 49 for controlling the direction of the presser foot support 27 are provided.

  As can be understood from FIG. 4, the needle bar 8 is supported by the sewing machine arm 7 so as to be movable up and down. The needle bar 8 has a hollow structure, and an introduction port 9 for passing the sewing thread T into the needle bar 8 is provided in the vicinity of the middle part of the needle bar 8, while the needle bar 8 has a lower part at the lower part thereof. A lead-out port 10 for taking out the sewing thread T introduced into the needle bar 8 through the introduction port 9 from the needle bar 8 is formed. A sewing needle 11 is fixed to the lower end portion of the needle bar 8, and a needle bar holder 12 for holding the needle bar 8 is fixed to a substantially middle part of the needle bar 8. The needle bar 8 is driven up and down by a needle bar drive mechanism 13 that uses the rotation of the sewing machine spindle 6 as a drive source. The needle bar drive mechanism 13 converts the rotation of the needle bar cam 14 fixed to the sewing machine main shaft 6 into the vertical movement of the elevating drive body 16 with respect to the guide shaft 15 supported by the sewing machine arm 7 in the vertical direction. This vertical movement is transmitted to the needle bar 8 via the needle bar holder 12. The raising / lowering driving body 16 is supported so as to be rotatable about its axis with respect to the guide shaft 15, and an engaging surface 16 a having a predetermined length in the vertical direction is provided on a side portion of the raising / lowering driving body 16. Is formed.

  As shown in FIG. 4, the boss portion 18 of the balance 17 is supported so as to be swingable about the axis of the balance shaft 19 fixed to the sewing machine arm 7 so as to be parallel to the sewing machine main shaft 6. That is, the balance 17 is repeatedly swung around the axis of the balance shaft 19 by a balance drive arm 21 that operates in conjunction with the rotation operation of the balance cam 20 fixed to the sewing machine main shaft 6.

  As shown in FIG. 5, the jump control motor 22 for performing jump control of the needle bar 8 to stop the operation of the sewing head H, that is, the transmission of the rotational drive of the sewing machine spindle 6 to the needle bar 8 is cut off. A drive arm 23 is fixed to the shaft of the motor 22 that controls the “jump state” in which the bar 8 does not move up and down in accordance with the rotation of the sewing machine main shaft 6. The motor 22 is driven and controlled by a predetermined jump signal, and the drive arm 23 can be rotated counterclockwise in FIG. That is, by rotating the drive arm 23 in the counterclockwise direction near the top dead center of the needle bar 8, the engagement surface 16a of the elevating drive body 16 is pushed by the tip of the drive arm 23. Rotates around the axis of the guide shaft 15. Then, the needle bar holder 12 of the needle bar 8 is released from the lifting / lowering drive body 16 (see FIG. 4), and transmission of the rotational drive of the sewing machine main shaft 6 is interrupted, so that the needle bar 8 enters a jump state. If the drive arm 23 is held at this rotational position, the needle bar 8 is in a continuous jump state. The vertical length of the engaging surface 16a of the elevating drive body 16 is set to a dimension that always faces the tip of the drive arm 23 in the entire range of the vertical stroke of the needle bar 8.

  Returning to FIG. 4, a support cylinder 24 is guided on the outer periphery of the needle bar 8 on the inner peripheral surface of the fixed sleeve 25 fixed to the lower part of the sewing machine arm 7, and the relative lifting operation with respect to the needle bar 8 and its operation. Rotation around the axis is possible. A ring 26 is fixed to the upper end of the support cylinder 24, and a presser foot support 27 is fixed to the lower end of the support cylinder 24. The presser foot support body 27 is formed in a bifurcated shape, a long key groove 27a is formed on one outer side surface, and a presser foot body 28 is fixed to the other lower portion. A guide 29 for guiding a string-like member fed out from a bobbin 34 (described later) to the needle base of the sewing needle 11 is fixed to the presser foot 28. A rotating cylinder 30 is provided on the outer periphery of the fixed sleeve 25 so as to be rotatable only about its axis. A pulley 31 is formed on the outer periphery of the upper end of the rotary cylinder 30, and a key member 32 that is engaged with the key groove 27 a of the presser foot support 27 is fixed to the lower end. A bobbin bracket 33 is fixed to the outer periphery of the rotary cylinder 30, and a bobbin 34 around which a string-like member to be sewn on the fabric by the sewing thread T is rotatably supported.

Next, a mechanism for raising and lowering the presser foot support 27 will be described mainly with reference to FIGS. 2, 5, and 6. FIG. 6 is an enlarged side view of a part of FIG.
As shown in FIG. 2, the front end portion (fork portion) of the drive arm 35 is engaged with the ring 26 of the support cylinder 24 so that power can be transmitted in the vertical direction. The drive arm 35 is attached to an elevating member 37 supported so as to be able to move up and down with respect to a guide shaft 36 arranged vertically with respect to the sewing machine arm 7. Further, a base elevating member 38 is supported on the guide shaft 36 so as to be movable up and down. The elevating member 37 is received by the base elevating member 38 via the block 39, and the elevating member 37 is pressed against the block 39 by the elasticity of the spring 40 provided on the guide shaft 36 between them. It is biased in the direction (downward).

  As shown in FIGS. 5 and 6, a drive lever 42 is fixed to the shaft of a motor 41 that is a drive source of a mechanism for raising and lowering the presser foot support 27. Is connected via a link member 43 to one end of a rotating arm 44 that is rotatably supported by the sewing machine arm 7. The other end of the rotating arm 44 is connected to the base lifting member 38 via a link member 45. As a result, when the motor 41 is driven, the turning arm 44 is reciprocally turned so that the base elevating member 38 and the elevating member 37 are raised and lowered along the guide shaft 36, and the support cylinder 24 is pressed through the drive arm 35. It is lifted and lowered together with the support body 27 (cloth presser body 28) (see FIG. 2). As shown in FIG. 6, the motor 41 is driven so that the rotating arm 44 reciprocally rotates between the position indicated by the solid line and the position indicated by the alternate long and short dash line in FIG. 6 during sewing. Then, the presser foot 28 is driven up and down between a bottom dead center indicated by a solid line and a top dead center indicated by a one-dot chain line in FIG. Further, when the sewing head is stopped or when the operation of the sewing head H is stopped, the rotation arm 44 is rotated to the position indicated by the two-dot chain line in FIG. 6 by driving the motor 41, and the presser foot 28 is moved to the two points in FIG. Retreat to the retreat position indicated by the chain line.

  Note that the bottom dead center of the presser foot 28 may rise depending on the type of string-like member to be sewn. In such a case, when the presser foot 28 hits the string-like member, the descending of the elevating member 37 stops, and only the base elevating member 38 descends against the elasticity of the spring 40 to allow the bottom dead center to rise. It can be done.

  Next, a mechanism for holding the sewing thread T as the cloth presser body 28 is retracted to the retracted position indicated by the two-dot chain line in FIG. 6 will be described. FIG. 7 is a partially enlarged view for explaining the operation of holding the sewing thread T. FIG. FIG. 8 is a front view of the sewing head H. Unlike FIG. 2, the sewing head H shows the sewing head H when the presser foot 28 is in the retracted position, that is, in the operation suspended state. FIG. 9 is a partial perspective view of the sewing head H shown in FIG. 2 and shows a case where the presser foot 28 is in the sewing position.

  As shown in FIGS. 2 and 6 to 9, an engagement piece 38 a is formed on the base elevating member 38. The sewing arm 7 is provided with a rotation holding member 46 having a contact side 46b that contacts the engagement piece 38a so as to be rotatable downstream of the balance 17 (see FIG. 9). The rotation holding member 46 is pivotally supported by a support member 47 fixed to the front surface of the sewing machine arm 7, and a rotation holding piece 46 a for holding the sewing thread T is formed on the rotation holding member 46. . Further, the rotation holding member 46 is urged to rotate clockwise in FIG. 9 or 2 by a torsion spring (not shown), and the contact side 46b abuts on the engagement piece 38a of the base elevating member 38. 9 or a pivot position as shown in FIG. Further, a fixed holding member 48 is fixed to the sewing machine arm 7. The fixed holding member 48 is formed with a fixed holding piece 48a for holding the sewing thread T with the rotation holding piece 46a of the rotation holding member 46. The rotation holding piece 46a and the fixed holding piece 48a are provided at positions where the sewing thread T guided to the introduction port 9 of the needle bar 8 can be held. Thus, the rotation holding member 46 is provided on the sewing machine arm 7 so as to hold the sewing thread T hung around the balance 17 at a position close to the sewing needle 11 downstream of the balance 17.

  The engagement piece 38a of the base elevating member 38 is located at the solid line position shown in FIG. 7 when the presser foot 28 is located at the bottom dead center, and is located at the one-dot chain line position shown in FIG. 7 when located at the top dead center. To do. That is, at the time of sewing, the engaging piece 38a moves up and down between the solid line position and the one-dot chain line position shown in FIG. On the other hand, at the time of sewing, the rotation holding member 46 is held at the rotation position indicated by the solid line in FIG. 7 since the contact piece 46b is received by the engagement piece 38a. In this state, the sewing thread T is not held, and therefore the sewing thread T is fed out as the sewing progresses. On the other hand, at the end of sewing or when the operation of the sewing head H is stopped, the engagement piece 38a moves to a position indicated by a two-dot chain line in FIG. Therefore, the contact between the contact side 46b and the engagement piece 38a is released, and the rotation holding member 46 is in contact with the fixed holding piece 48a of the fixed holding member 48 in FIG. It is rotated to the rotation position shown. Then, the sewing thread T is held between the rotation holding piece 46a and the fixed holding piece 48a. Therefore, the sewing thread T is not fed out when the sewing is finished or when the operation of the sewing head H is stopped.

  A shaft 50 is connected to the shaft of a motor 49 for controlling the direction of the presser foot support 27, and a lower portion of the shaft 50 is rotatably supported by a base member 51 fixed to the sewing machine arm 7. . A driving pulley 52 is fixed to the lower end portion of the shaft 50, and a timing belt 53 is stretched between the driving pulley 52 and the pulley 31 of the rotary cylinder 30. Accordingly, when the motor 49 is driven, the rotary cylinder 30 reciprocates and the direction of the presser foot support 27 and the guide 29 is controlled via the key member 32.

  Next, an operation procedure when the string-like member is sewn in the multi-head sewing machine having the above-described configuration will be briefly described. In the multi-head sewing machine having the above-described configuration, when sewing the string-like member, the sewing thread T is passed through the needle hole of the sewing needle 11 of each sewing head H, and the bobbin 34 around which the string-like member is wound is set. The sewing thread T is fed from a supply section (not shown) provided above the upper frame 2 and passes through a thread tension section on the upper part of the sewing machine head H. As shown in FIG. After passing through the middle thread path 55 provided on the front surface of the arm 7 and the tip of the balance 17 in this order, the needle bar 8 is led out from the outlet port 10 through the needle bar 8 through the needle bar 8, and into the needle hole of the sewing needle 11. Pass through. The bobbin 34 around which the string-like member is wound is set on the bobbin bracket 33, and the string-like member is drawn out from the bobbin 34, passed through the guide 29, and guided to the needle base of the sewing needle 11. When the sewing machine is operated by operating the start switch of the sewing machine, the sewing machine spindle 6 is rotated, the needle bar 8 (sewing needle 11) is driven up and down, and the balance 17 is swung. The cloth presser body 28 is driven to move up and down between the solid line position and the one-dot chain line position in FIG. The rotation cylinder 30 is rotationally controlled by a motor 49, and the direction is controlled so that the bobbin 34 and the guide 29 are always positioned on the front side in the sewing advance direction. Then, the hook 3 is rotated in synchronism with the raising / lowering drive of the needle bar 8 (the sewing needle 11), and the sewing frame 5 is driven in the front / rear / right / left directions, whereby the sewing product stretched and held by the sewing frame 5 is achieved. The string-like member is sewn.

  Next, an operation procedure when only a part of the plurality of sewing heads H is operated and the operation of the remaining sewing heads H is stopped will be described. In the sewing machine head H to be stopped, the needle bar 8 is brought into a continuous jump state by driving the motor 22 and the cloth presser body 28 is retracted to the retracted position indicated by the two-dot chain line in FIG. When the presser foot 28 is retracted to the retracted position, the contact between the engagement piece 38a of the base lifting member 38 and the contact side 46a of the rotation holding member 46 is released, and the rotation holding member 46 is moved to the rotation holding piece. 46a and the fixed holding piece 48a of the fixed holding member 48 are rotated to a rotation position indicated by a two-dot chain line in FIG. Thereby, the sewing thread T guided to the introduction port 9 of the needle bar 8 is sandwiched and held between the rotation holding piece 46a and the fixed holding piece 48a.

  As described above, in the multi-head sewing machine according to the present invention, the sewing thread T guided to the introduction port 9 of the needle bar 8 is sandwiched between the rotation holding piece 46a and the fixed holding piece 48a when the operation of the sewing head H is suspended. Since it is held, the sewing thread T will not be pulled out of the needle hole of the sewing needle 11 even if the balance 17 swings in the sewing machine head H that is not in operation. Thereby, it is not necessary to provide a blocking mechanism for stopping the swinging of the balance 17, and the structure of the sewing head H is simplified and the cost can be reduced. In addition, since the sewing thread T is held in conjunction with the retracting operation of the presser foot 28, it is not necessary to provide a drive source for holding the sewing thread T, and the cost can be reduced. This makes it possible to prevent forgetting of operations caused by performing the operation.

In the above-described embodiment, an example is shown in which the present invention is applied to a multi-head sewing machine having only a sewing head H that can sew a string-like member, but the sewing head H that can sew a string-like member and an embroidery sewing machine are shown. You may make it apply only to the sewing machine head H which can sew a string-like member in the multi-head sewing machine provided with the head alternately.
The sewing thread T is held by rotating the rotation holding member 46. However, the present invention is not limited to such a form, and the sewing thread T may be changed to hold the sewing thread T by another form such as a slide.
In each of the above-mentioned drawings, it goes without saying that 56 is a known needle plate fixed to the upper surface of the pot base 4.

It is a front external view which shows one Example of the multi-head sewing machine which concerns on this invention. It is a front view of the sewing machine head arrange | positioned at the multi-head sewing machine shown in FIG. It is a left view of a sewing machine head. It is a left side sectional view of a sewing machine head. It is the side view which fractured and expressed a part of sewing machine head. It is the side view which expanded and showed a part of FIG. FIG. 6 is a partially enlarged view for explaining an operation of holding a sewing thread. It is a front view of a sewing machine head in the operation halt state. It is a partial perspective view of the sewing machine head when the presser foot is in the sewing position.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Sewing machine table, 2 ... Upper frame, 3 ... Hook, 4 ... Pot base, 5 ... Sewing frame, 6 ... Sewing spindle, 7 ... Sewing arm, 8 ... Needle bar, 9 ... Inlet, 10 ... Outlet, 11 ... Sewing needle, 12 ... Needle bar holding mechanism, 13 ... Needle bar drive mechanism, 14 ... Needle bar cam, 15 ... Guide shaft, 16 ... Lifting drive, 17 ... Balance, 18 ... Boss, 19 ... Balance shaft, 20 ... Balance cam, 21 ... Balance drive arm, 22 ... Needle bar jump control motor, 23 ... Drive arm, 24 ... Support cylinder, 25 ... Fixed sleeve, 26 ... Ring, 27 ... Work clamp support, 27a ... Keyway, 28 DESCRIPTION OF SYMBOLS ... Material holding body, 29 ... Guide, 30 ... Rotary cylinder, 31 ... Pulley, 32 ... Key member, 33 ... Bobbin bracket, 34 ... Bobbin, 35 ... Drive arm, 36 ... Guide shaft, 37 ... Lifting member, 38 ... Base Elevating member, 38a ... engagement piece, 39 ... block, 40 Spring, 41 ... cloth presser support raising / lowering motor, 42 ... drive lever, 43 ... link member, 44 ... rotating arm, 45 ... link member, 46 ... rotating holding member, 46a ... rotating holding piece, 46b ... Contact piece 47... Support member 48. Fixed holding member 48 a. Fixed holding piece 49. Motor for controlling the presser body direction 50. Shaft 51. Base member 52 Drive pulley 53 53 Timing belt 54 ... Upper thread path, 55 ... Middle thread path, 56 ... Needle plate, H ... Sewing head, T ... Sewing thread

Claims (5)

A sewing machine comprising a sewing head having a needle bar that is driven up and down together with a sewing needle attached to a lower end, and a balance that is swung in synchronization with the vertical driving of the needle bar,
A holding member for holding the sewing thread stretched over the balance at a position downstream from the balance and upstream from the sewing needle of the needle bar, and in synchronism with the vertical movement of the needle bar during operation of the sewing machine head A cloth presser body that is driven up and down, but is retracted and moved to an upper retracted position when the sewing machine head is suspended , is provided in the sewing head.
The holding member is selectively displaceable to either a first position that does not hold the yarn or a second position that holds the yarn,
An interlocking mechanism for positioning the holding member at the second position in conjunction with the movement of the cloth presser to the retracted position is further provided in the sewing head;
When the movement of the needle bar is stopped and the operation of the sewing head is stopped, the sewing thread is held by the holding member positioned at the second position in conjunction with the movement of the cloth presser to the retracted position. The sewing machine is characterized in that the movement of the sewing thread downstream of the balance is stopped regardless of the movement of the balance.   The sewing machine according to claim 1, wherein the holding member is provided in the vicinity of a thread introduction port of the needle bar. The sewing head further includes a rotating body that is assembled coaxially with the needle bar and is free to rotate about its axis, and is rotated together with the rotating body to the needle base position of the sewing needle. And a guide for guiding the sewing member, the rotation of the rotating body is controlled according to the movement direction of the fabric based on the sewing pattern data, and the guide direction of the string-like sewing member to the needle base of the sewing needle is appropriate The sewing machine according to claim 1 or 2 , wherein the string-like member is sewn to the fabric by main sewing while changing the direction of the guide so that The sewing machine, sewing machine according to any one of claims 1 to 3 comprising a plurality of the sewing head. A needle bar that is driven up and down together with a sewing needle mounted at the lower end, a balance that is swung in synchronization with the vertical drive of the needle bar, and an axis that is assembled coaxially with the needle bar. A rotating body that can freely rotate around and a guide that is rotated together with the rotating body to guide the string-like member to the needle base position of the sewing needle, and the rotation according to the movement direction of the fabric based on the sewing pattern data A plurality of sewing heads that sew the string-like member to the fabric by main sewing while controlling the rotation of the body and changing the guide direction so that the guide direction of the string-like member to the needle base of the sewing needle is appropriate. In the multi-head sewing machine provided,
A holding member for holding the sewing thread stretched over the balance downstream from the balance ;
While the sewing machine head is in operation, the cloth is driven up and down in synchronization with the vertical movement of the needle bar, and when the sewing machine head is not in operation, the cloth is retracted to the upper retreat position and is not driven up and down. The presser foot,
An interlocking mechanism that interlocks the holding member so as to hold the sewing thread stretched over the balance in accordance with the retraction operation of the presser foot, and is provided in the sewing head.
In the sewing machine head that stops operation, the movement of the sewing thread downstream of the balance is stopped by holding the sewing thread by the holding member that is interlocked with the movement of the cloth presser to the retracted position. Multi-head sewing machine.

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