KR101398081B1 - Yarn controlling device of chain stitch sewing machine - Google Patents

Abstract

The present invention is intended to more appropriately prevent the looper thread from being wound.

The sewing machine of the present invention comprises a lower shaft 2, a looper which swings in conjunction with rotation of the lower shaft 2, two thread passing portions 11 and 12, two thread passing portions 11 and 12, Two thread control cams 13 and 14 provided on the lower shaft 2 such that the looper thread L across the outer thread of the looper chamber L slidably contacts the outer periphery of the looper thread L and the thread control cams 13 and 14, And a thread guide member 15 having an elongated hole portion 15a for reciprocating the louper chamber L sliding on the cams 13 and 14 along a predetermined path, The notched portion 15b is formed on the inner side edge portion 15d on the lower shaft side of the base portion 15a.

Description

BACKGROUND OF THE INVENTION Field of the Invention [0001] The present invention relates to a yarn control device for a round yarn sewing machine,

The present invention relates to a yarn control device of a round bar sewing machine for controlling the tension of a looper thread.

A sewing machine having an overlock stitch or a double chain stitch (double round bar) provided with a looper swinging below the needle plate is characterized in that the loop of the upper thread passed through the sewing needle is captured by a looper, The sewing needle is picked up by repeating the operation of sewing.

As shown in Fig. 13 (a), two thread passing members 111 and 112 as a path of the looper chamber L1 and two thread passing members 111 and 112 as a path of the looper chamber L1 are provided as a thread control device for keeping the tension of the looper thread constant. And two thread control cams (113, 114) installed on the outer periphery of the louvre chamber (L1) passing between the thread passing portions and slidably in contact with each other; A sewing machine having a yarn guide device 115 having a yarn guide member 115 having an elongated hole portion 115a through which the looper thread L1 to be contacted is formed is widely used.

In the thread control device 110, the looper chamber L1 unwound from a bobbin (not shown) disposed on the right side of Fig. 13A is inserted into the hole portion 111a of the thread passing portion 111, Hole 115a of the thread guide member 115 and the hole portion 112a of the thread passing portion 112 in this order. The thread control cams 113 and 114 are slidably engaged with the looper chamber L1 between the thread passing portion 111 and the thread guide member 115 and between the thread passing portion 112 and the thread guide member 115, And the tensile force is applied to the looper chamber L1 to maintain the tension of the looper chamber L1.

However, during the sewing operation of the sewing machine using the yarn control device 110, the looper chamber L1 may be cut off from the looper side more than the yarn passage portion 111 due to fluctuation of the looper. In this case, as shown in Fig. 13 (b), the bobbin side portion of the looper chamber L1 that caused the thread cutting is drawn from the thread guide member 115 and the thread passing portion 112, L1 are wound while being in sliding contact with the shaft portion 102a between the thread control cams 113 and 114 and are wound around the shaft portion 102a in accordance with the rotation of the lower shaft 102 . The removal of the looper chamber L1 wrapped around the shaft portion 102 in this manner is extremely troublesome and takes a lot of time, which gives a great burden to the operator and significantly reduces the efficiency of the sewing work. When the looper thread L1 wound on the shaft portion 102a is cut by using a knife or the like during the removal, the knife touches the surface of the thread control cams 113 and 114 in a wrong operation, Something happens. At this time, in the sewing operation performed after the looper thread is removed, the looper thread L1 is easily caught in the wound portion, which may easily cause the looper thread L1 to be cut and wound.

Therefore, a thread cutting blade that operates to repeat contact and non-contact with the looper thread L1 on the path of the bobbin-side looper chamber L1 is provided separately from the thread control cam 114, It is known that the knife edge contacts the looper chamber L1 to cut the looper chamber L1 (see, for example, Patent Document 1).

[Patent Document 1] Japanese Utility Model Publication No. H3-55077

However, in the conventional sewing machine according to Patent Document 1, when the looper chamber (L1) is pulled out when the knife provided substantially parallel to the path of the looper chamber (L1) is in contact with the looper chamber . For this reason, depending on the thickness and material of the looper chamber L1, the looper chamber L1 slips with respect to the knife edge, and the knife edge does not function sufficiently, so that the thread cutting may not be performed. Therefore, when the cutting is not performed, a large amount of the looper chamber L1 is wound up. However, there is a problem that it is very troublesome to remove the looper chamber L1 that has been wound.

In addition, since the thread cutting blade is separately provided on the path of the looper chamber L1, there is a problem that the design of the sewing machine is limited in order to provide the installation space for the blade. The sewing machine of the prior art according to Patent Document 1 is designed so that the looper chamber L1 is cut only when the knife is wound around the looper chamber L1 by repeatedly contacting and not contacting the looper chamber L1 There is a problem in that not only the design of the sewing machine becomes complicated but also the construction for cutting the thread is expensive.

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to more appropriately prevent winding of a looper thread.

According to a first aspect of the present invention, there is provided a sewing machine comprising a lower shaft rotated by rotation of a sewing machine motor, a looper swinging in conjunction with rotation of the lower shaft, two thread passing portions, Two thread control cams provided on the lower shaft so that the looper chamber crossing between the two thread passing portions is in sliding contact with the outer periphery thereof; And a thread guide member having an elongated hole for reciprocating the looper chamber in a predetermined direction while allowing the looper chamber to be in contact therewith to be inserted therethrough, wherein a tension is applied to the looper chamber in accordance with a change in diameter of the two thread cams Wherein the thread guiding member (15) has an inner edge portion on the lower shaft side along the longitudinal direction of the elongated hole portion And a thread cutting means (15b) provided on the way to cut the looper thread.

The invention according to claim 2 is characterized in that, in the yarn control machine of the round barrel sewing machine according to claim 1, the yarn feeder And a seal catching member (20) fixed to the frame at a position between the lower end and the lower shaft so as to catch the end of the looper chamber.

The invention according to claim 3 is the yarn control device of the round bar sewing machine according to claim 1, further comprising: a first cylindrical part (14a) provided on a side of the yarn control cam side of the looper thread supply source side, And a cutting member (21) disposed in the vicinity of the outer circumferential surface of the one cylindrical portion and capable of cutting the looper chamber.

The invention according to claim 4 is characterized in that the yarn control device of the circular barrel sewing machine according to claim 3 is provided with a second cylindrical part (4) fixed to the sewing machine frame and allowing the lower shaft to pass therethrough, And one end of the cylindrical portion is inserted into an end portion of the first cylindrical portion located on the looper chamber supply source side.

According to a fifth aspect of the present invention, in a yarn control device for a round bar sewing machine according to claim 1, the yarn cutting means includes a yarn cutting means for cutting the looper thread in accordance with a change in diameter, And a thread hooking portion 15b for cutting the looper thread according to the change of the diameter.

The invention according to claim 6 is characterized in that, in the yarn control device of the round barreling machine according to claim 5, the yarn cutting means is a concave part formed in the inner side edge part.

The invention according to claim 7 is characterized in that, in the yarn control device of the round barreling machine according to claim 5, the yarn cutting means is a convex part formed in the inner edge part.

According to the invention defined in claim 1, when the cut looper chamber is wound around a shaft portion of a gap formed between two thread control cams, the thread cutting means cuts the looper thread. At this time, the thread cutting means is provided on the inner side of the inner edge portion which becomes the lower shaft side among the two inner edge portions along the longitudinal direction of the elongated hole portion formed in the thread guide member. That is, the yarn cutting means is provided so as to cut the looper chamber only when one end of the looper chamber is pulled toward the lower shaft axis by winding the cut looper chamber onto the lower shaft. This prevents the thread cutting means from unnecessarily cutting the looper thread during a normal sewing operation and only when the cut looper thread is wound around the shaft portion of the gap between the two thread control cams for any reason, . Therefore, the reliability of the sewing machine is further improved.

Further, the thread cutting means cuts the looper thread before a large amount of the looper thread is wound and attached. At this time, the supply-side end portion of the looper chamber cut by the yarn cutting means is removed by the yarn control cam on the looper thread supply source side among the two yarn feed control cams, and is not wound on the shaft portion again. As a result, a very small amount of the looper thread wound around the shaft portion can be easily removed. Therefore, the conventional problem that the removal of the looper thread is very complicated because a large amount of the looper thread is wound up can be solved, and the reliability and comfort of the sewing machine are greatly improved.

Further, since the thread cutting means is provided at the inner edge portion of the elongated hole portion formed in the thread guide member, it is not necessary to secure the space for securing the member and the blade for fixing the separate blade as in the prior art, The degree of freedom is further improved.

Further, since the thread cutting means does not require a mechanism for repeating contact and non-contact with the looper thread as in the prior art, the structure for cutting the looper thread is very simple, and the design of the sewing machine is further simplified However, it is possible to provide a sewing machine capable of cutting the looper thread when the looper thread is wound at a very low cost.

Further, the yarn cutting means is not limited to a knife shape. The structure may be such that the movement of the looper chamber moving along the inner edge portion on the lower shaft side is captured by the seal control cam on the looper thread supply source side and blocked while the movement is taken as in the invention described in claim 5. As a result, the looper chamber can be pulled out by pulling the looper chamber by the actual control cam on the side of the lower shaft and the looper chamber supply source, thereby functioning as a thread cutting means.

According to the invention defined in claim 2, the yarn catching member is provided closer to the looper thread supply source than the outer periphery of the yarn control cam on the looper thread supply source side, and extends from the outer periphery to the lower shaft. In other words, the end portion of the looper chamber that is spaced apart from the side of the looper chamber supply source side of the thread control cam on the side close to the looper thread supply source can be captured. Thereby, in the gap formed between the side surface of the looper thread supply side of the looper thread supply side and the bearing provided on the side surface of the bearing rotatably supporting the lower shaft, and the end portion of the looper thread It is possible to prevent winding. Therefore, the problem that the removal of the looper thread is very complicated due to the large looper thread being wound around the gap can be solved, and the reliability and comfort of the sewing machine are greatly improved.

According to the invention defined in claim 3, the first cylindrical portion is provided integrally with the thread control cam on the side of the looper thread supply side of the thread control cam on the looper thread supply side, and allows the lower thread to be inserted therethrough. That is, the first cylindrical portion is provided so as to cover the outer peripheral portion of the lower shaft 2 on the side of the side of the looper chamber supply source side of the thread control cam. Thus, when the end of the cut looper chamber is located on the side of the looper chamber supply source side of the thread control cam, the looper chamber is wound around the outer circumferential portion of the first cylindrical portion. Therefore, it is possible to prevent the looper thread from being wound around the lower shaft. At this time, since the knurled part disposed close to the outer peripheral part of the cylindrical part of the cutting member cuts the looper chamber wound around the first cylindrical part, the looper chamber is cut without being wrapped around the outer peripheral part of the first cylindrical part. Therefore, when the looper thread is broken, the looper thread is wound around the lower shaft in a large amount, thereby eliminating the problem that the looper thread is very complicated to be removed. Thus, the reliability and comfort of the sewing machine are greatly improved.

According to the invention recited in claim 4, the end of the first cylindrical portion on the looper chamber supply source side is arranged so as to insert a second cylindrical portion fixed to the sewing machine frame on the inside thereof. For example, the end of the first cylindrical portion on the looper chamber supply side side inserts the bearing of the lower shaft into the inside thereof. That is, the outer circumferential surface of the lower shaft is completely covered by the first cylindrical portion and the second cylindrical portion between the side surface of the looper thread supply side of the yarn control cam on the looper thread supply side and the bearing. This prevents the end portion of the looper chamber, which is cut off from the side surface of the looper chamber supply source side of the looper chamber supply source side and the outer circumferential surface of the lower shaft between the bearings, from being wound. Therefore, the problem that the removal of the looper thread is very complicated due to the large looper thread being wound around the gap can be solved, and the reliability and comfort of the sewing machine are greatly improved.

According to the invention defined in claim 5, the yarn cutting means is a yarn hooking part for hanging a looper thread. That is, when the cut looper thread is wound around the lower shaft to pull the one end of the looper chamber toward the lower shaft side, the looper thread is wound on the inner edge of the lower shaft side of the long hole portion of the thread guide member, Lt; / RTI > At this time, the looper thread tends to be pulled by the looper thread wound around the shaft portion of the clearance formed between the two thread control cams by the rotation of the lower shaft, So that it receives a tensile force resulting from the change of the path of the looper thread. That is, the looper thread is tensioned in two different directions with the threaded portion as a supporting point. As a result, the looper thread is torn off by the threading portion and cut. Therefore, since it is not necessary to cut the thread cutting means into a knife shape, the thread cutting means can be provided at a lower cost.

According to the invention defined in claim 6, since the yarn cutting means is a recess formed in the inner edge portion of the elongated hole portion formed in the yarn guide member, the wound looper thread can be cut without providing a separate blade or the like .

In addition, the actual thread cutting means can be provided without significantly changing the design of the conventional thread control apparatus. Therefore, the thread cutting means can be provided at a lower cost.

According to the invention defined in Claim 7, since the thread cutting means is a protruding portion formed in the inner edge portion of the elongated hole portion formed in the thread guide member, the threaded looper thread can be cut without providing a separate blade or the like .

In addition, the actual thread cutting means can be provided without significantly changing the design of the conventional thread control apparatus. Therefore, the thread cutting means can be provided at a lower cost.

(Overall configuration of an embodiment of a sewing machine according to the present invention)

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

The sewing machine according to the present invention is provided with a thread control device 10 for controlling the tension of the looper chamber L by using a looper thread L guided by a looper provided below the needle plate It is a sewing machine.

1 is a perspective view showing a configuration of a yarn control device 10 provided in a sewing machine according to the present invention.

The sewing machine includes a lower shaft 2 provided inside the bed portion of the sewing machine frame and a looper having a sickle-shaped protrusion pivotally linked to the rotation of the lower shaft 2 below the needle plate provided on the upper surface of the bed portion A bobbin (not shown) as a supply source of the looper chamber L guided by the looper and a yarn control device 10 provided so as to be positioned on the path of the looper chamber L between the looper and the bobbin have.

In addition, the sewing machine has a well-known structure in which the needle bar for holding the sewing needle at the lower end moves up and down in association with the upper shaft rotated by the sewing machine motor, and the rotation of the upper shaft is transmitted to the lower shaft 2.

The looper disposed below the needle bar has a hole portion through which the looper chamber L is passed at the tip end of the sickle-shaped projection, and is swung by the rotation of the lower shaft 2, Looper.

Further, the rotation of the lower shaft 2 causes the thread control device 10 to operate. The operation of the thread control device 10 will be described later.

(Thread control device)

Next, the actual control device 10 will be described in detail.

1, the yarn control device 10 includes yarn passage portions 11 and 12 provided above the lower shaft 2 and having holes 11a and 12a serving as paths of the looper chamber L, 12 and a threaded portion L which is fixed to the lower shaft and is shielded between the threaded portions 11 and 12 so that its outer periphery slidably contacts a looper chamber L passing through the holes 11a and 12a, A thread guide member 15 provided between the cams 13 and 14 and the thread control cams 13 and 14 and having elongated hole portions 15a serving as a path of the looper chamber L, And 12, and a pivoting member 16 that rotatably supports the thread guide member 15 up and down. The sewing machine includes bearings 3 and 4 fixedly held on the sewing machine frame and rotatably supporting the lower shaft 2 and a louver chamber (not shown) provided on the sewing machine frame and extending from the bobbin as a supply source of the looper chamber L A seal catching member 20 which covers the clearance 2b formed in the bearing 4 between the seal control cam 14 and the bearing 4 from the upper surface thereof; See Fig. 5).

The thread passing portions 11 and 12 and the thread guide member 15 are supported by the tiltable member 16. 1) is rotatably supported on the sewing machine frame so that the front end (the front side in Fig. 1) of the pivoting member 16 is moved toward and away from the lower shaft 2 in the vertical direction . The thread passing portions 11 and 12 and the thread guide member 15 are provided at the tip end portion of the tiltable member 16 and are positioned at the time of use at which the tiltable member 16 approaches the lower shaft 2 by the rotation of the tiltable member 16 (Fig. 1), and a non-use position (see Fig. 7) which is spaced upward from the lower shaft 2 for maintenance or the like.

As described above, the thread passing portions 11 and 12 are formed with the holes 11a and 12a serving as the paths of the looper chamber L. Further, the thread guide member 15 is provided with an elongated hole portion 15a serving as a path of the looper chamber L. The loupe chamber L led out from the seal path portion 5 first passes through the hole portion 12a and then through the long hole portion 15a and finally through the hole portion 11a to the looper . At this time, the looper chamber L is in sliding contact with the outer peripheral portion of the thread control cam 14 between the hole 12a and the long hole 15a, and between the long hole 15a and the hole 11a, And is in sliding contact with the outer peripheral portion of the control cam 13.

The thread guide member 15 is inclined so that the tip side (the lower shaft side end portion 15c side) of the elongated hole portion 15a is higher (the upper side in Fig. 2) when the pivoting member 16 is in the use position Respectively.

As shown in Fig. 4, the outer peripheral portion of the thread control cams 13 and 14 which rotate with the clockwise rotation of the lower shaft 2 is located on the lower side (lower shaft side) of the longer hole portion 15a, (Needle plate side) of the long hole portion 15a toward the inner side edge portion 15e of the long hole portion 15a.

A notch 15b, which is a concave portion formed by cutting downward, is formed in the longitudinal middle portion of the inner side edge portion 15d on the lower side of the long hole portion 15a. The notch 15b will be described later.

The yarn control cams 13 and 14 are of the same shape and the shape of the outer peripheral portion is changed so that a part of the outer periphery is larger in diameter than the other portion (small diameter portion). 3 shows a state in which the large-diameter portion of the thread control cams 13, 14 is in contact with the looper chamber L. As shown in Fig.

The thread control cams 13 and 14 rotate with the lower shaft 2 as a rotation axis, and the outer peripheral portion of the threaded control cams 13 and 14 is in sliding contact with the looper chamber L at the same time as the rotation. That is, when the actual control cams 13 and 14 are rotated by the rotation of the lower shaft 2, the timing at which the small diameter portions of the thread control cams 13 and 14 are in sliding contact with the looper chamber L (The state of Fig. 3) at which the large-diameter portion of the thread control cams 13 and 14 is in sliding contact with the looper chamber L, And is changed along the longitudinal direction within the elongated hole portion 15a of the base plate 15.

At this time, the timing of the diameter change of the thread control cams 13, 14 with respect to the looper chamber L corresponds to the looper oscillation timing.

For example, when the looper is retracted relative to the sewing needle, the distance between the looper and the thread control device 10 is shortened. At this time, the thread control cams 13 and 14 are operated so that the large diameter portion makes sliding contact with the looper chamber L. [ The looper chamber L from the hole portion 11a of the thread passing portion 11 to the looper is pulled by the thread control cam 13 so that the looper chamber L between the looper and the hole portion 11a L, the looper chamber L is not loosened. At this time, the thread control cam 14 pulls the looper chamber L on the thread path section 5 side. Thus, the looper chamber L is drawn out from the bobbin as the supply source of the looper chamber L.

On the other hand, when the looper advances relative to the sewing needle, the distance between the looper and the yarn control device 10 becomes longer. At this time, the small-diameter control cams 13 and 14 are in sliding contact with the looper chamber L so that the looper chambers 13 and 14 move to the small- (L) is loosely stretched by the looper, and tension is applied. Thus, the tension of the looper chamber L corresponding to the swinging motion of the looper is maintained.

The looper chamber L in the case where the thread cut is not performed during a normal sewing operation is formed by sliding contact with the outer peripheral portion of the thread control cams 13 and 14 so that the long threaded portion 15a ). ≪ / RTI > More specifically, the route of the louper chamber L shown in Fig. 4 (c) is obtained from the route of the louper chamber L shown in Fig. 4 (a) L). 4 (c), since the looper chamber L is held at the outer peripheral portion of the thread control cams 13 and 14, the long hole portions 15a of the thread guide member 15 The inner side edge portion 15d of the lower side is not displaced. That is, when the thread cutting is not performed, the looper chamber L is not caught by the notch 15b.

(Cutting and winding of looper thread)

Generally, cutting of the looper chamber L during the sewing operation by the sewing machine often occurs on the side closer to the looper (left side in Fig. 5) than the thread control cam 13. [ 5 (b), when the looper chamber L is cut, the cut end portion L1 of the looper chamber L is moved in the direction And is removed from the hole portion 11a of the thread passing portion 11 and is removed. 5 (c), when the end portion L1 of the loupe chamber L is separated between the thread control cam 13 and the thread guide member 15, the end portion L1 is in contact with the end portion L1 Is wound around the outer periphery of the shaft portion 2a by sliding contact with the shaft portion 2a between the thread control cams 13 and 14 and the thread is pulled out from the bobbin side (right side in Fig. 5) It becomes more wounded.

(Thread cutting means)

The looper chamber L is brought into contact with the inner side edge portion 15d on the lower side of the long hole 15a of the thread guide member 15 when the end portion L1 falls as described above. When the lower shaft 2 continues to rotate in a state in which the looper chamber L starts to be wound around the shaft portion 2a, the looper chamber L is moved in the direction in which the thread guide member 15 Is guided through the path of Figs. 6 (a) to 6 (c) with respect to the long hole portion 15a. That is, when the thread control cam 14 and the looper chamber L are in sliding contact with each other in the state where the end portion L1 is wound around the shaft portion 2a, the path of the looper chamber L is located below the long hole portion 15a And is displaced so as to approach the right side from the left side of Fig. 6 while being in sliding contact with the inner side edge portion 15d. 6 (b), the loupe chamber L displaced so as to be in sliding contact with the inner edge portion on the lower shaft side of the elongated hole portion 15a extends downward toward the inner edge portion 15d And is caught by the cut-out portion 15b.

The notch portion 15b is erected in a vertical state with its rear end edge in the moving direction. 6 (c), the looper chamber L is engaged with the rear end edge of the notch portion 15b to prevent the looper chamber L from moving rearward in the moving direction, The lower shaft 2 further rotates and tension is applied by the thread control cam 14 so that the looper chamber L is pulled off by the rear end edge of the notch 15b.

That is, the looper chamber L on the path from the notch 15b to the shaft 2a is pulled in the direction of arrow B. Therefore, the looper chamber L is stretched in the direction of the arrow A and the direction of the arrow B with the notch 15b as a fulcrum, so that a very strong engagement force acts on the position of the notch 15b. Due to such a tension, the looper chamber L is torn off and cut with the notch 15b as a fulcrum. Therefore, the notch 15b functions as a "threading portion" and a "thread cutting means".

2, the notch 15b is formed so that the notch 15b is not slipped out of the notch 15b before the looper chamber L caught by the notch 15b is cut off, And the protruding portion 15f formed by the inner side edge portion 15d of the lower shaft side of the elongated hole portion 15a is greater than 0 degrees and less than or equal to a right angle desirable.

The length of the looper chamber L wound around the shaft 2a is determined by cutting the looper chamber L from the end L1 on the looper chamber supply source side when the looper chamber L is broken by the notch 15b Only the length to the end of the looper chamber L is obtained. Thereby, even if the lower shaft 2 rotates to some extent after the looper chamber L is broken during the sewing operation of the sewing machine, the amount of the looper chamber L wound around the shaft portion 2a is small So that the looper chamber L wound around the shaft portion 2a can be easily removed.

When the looper chamber L wound around the shaft portion 2a is to be removed, the operation of the sewing machine is stopped, and then a lid portion (not shown) provided on the upper surface of the bed portion located above the thread control device 10 is opened , The pivoting member 16 is rotated upward as shown in Fig. 7, thereby facilitating the manual operation of each part of the thread control device 10. [ Then, the looper chamber L wound around the shaft portion 2a is removed by a tweezers or the like.

The end portion L2 (see FIG. 8) of the looper chamber L side cut off by the notch 15b will be described later.

(Thread catching member)

Next, the seal catching member 20 will be described in detail.

5, the seal catching member 20 is formed so as to cover the upper half of the clearance 2b formed between the seal control cam 14 and the bearing 4 in the outer peripheral surface of the bearing 4 Is installed. In addition, the surface of the yarn capturing member 20 is formed with a band-shaped brim along the arc of the outer periphery of the bearing 4, and when the end of the yarn falls on the surface, the end of the yarn is caught by the frictional force . The seal catching member 20 is disposed between the side end portion and the seal control cam 14 so as to prevent a clearance between the side end of the seal catching member 20 on the seal control cam 14 side and the seal control cam 14. [ As shown in Fig.

As shown in Fig. 8 (a), the looper chamber side end portion L2 of the looper chamber L cut by the notched portion 15b is removed by the thread control cam 14. Fig. At this time, as shown in Fig. 8 (b), the looper chamber L falls into the gap between the seal control cam 14 and the tiltable member 16. In this case, as shown in Fig. 8 (c), the end portion L2 is separated from the upper surface portion of the yarn capturing member 20, is caught by the bristles formed on the upper surface portion, and is not moved thereafter. That is, since the ends of the looper chamber L are caught by the seal catching member 20, they are not caught between the clearance 2b formed between the seal control cam 14 and the bearing 4. Therefore, the end portion L2 of the looper chamber L cut by the notch 15b is not wound again, and the looper chamber L that has been cut more easily can be processed.

When the looper chamber L is cut off, the end portion L1 on the looper thread supply side is removed by the thread control cam 14 without being wound around the shaft portion 2a and the thread control cam 14 and the pivoting member 16 In some cases. In this case, the end portion L1 is caught by the seal catching member 20, and then is not moved. Therefore, the looper thread L is not wound.

The processing of the end portions L1 and L2 of the looper chamber L captured by the seal catching member 20 is substantially the same as the processing of the looper chamber L wound around the shaft portion 2a. That is, after stopping the operation of the sewing machine, a lid portion (not shown) provided on the upper surface of the bed portion located above the thread control device 10 is opened to rotate the tiltable member 16 upward Thereby facilitating the manual operation of each part of the yarn control device 10. The end portions L1 and L2 of the loupe chamber L captured by the yarn catching member 20 are removed by a tweezers or the like and the loupe chamber L is then inserted into the hole portion 12a and the long hole portion 15a, And the louver chamber L is guided by the operator so as to pass through the hole portion 11a and lead out to the looper.

(Function and effect of the sewing machine according to the above-described embodiment)

According to the above-described embodiment, when the cut loupe chamber L is wound around the shaft portion 2a between the two thread control cams 13 and 14, the notch 15b is hooked on the looper chamber L Cut it. The notched portion 15b is formed in the inner side edge portion 15d which is the lower side of the two inner side edge portions along the longitudinal direction of the elongated hole portion 15a formed in the thread guide member 15. [ That is, only when the cut looper chamber L is wound around the lower shaft so that one end of the looper chamber L is pulled toward the lower shaft side, the notch 15b is set so as to cut the looper chamber L . This makes it possible to prevent the looper chamber L from being cut off for any reason between the thread control cams 13 and 14 The looper chamber L is cut off only when it is wound around the shaft portion 2a. Therefore, the reliability of the sewing machine is further improved.

The notch 15b cuts the looper chamber L before a large amount of the looper chamber L is wound by the rotation of the lower shaft 2. At this time, the end portion L2 of the looper chamber L side cut off by the notch 15b on the looper chamber supply side side is removed by the thread control cam 14, and is not wound on the shaft portion 2a again. As a result, the looper chamber L wound around the shaft portion 2a becomes very small, so that the looper chamber L can be easily removed. Therefore, the conventional problem that a large amount of the looper chamber L is wound up and the removal of the looper chamber L becomes very complicated can be solved, and the reliability and comfort of the sewing machine can be greatly improved.

Since the notch 15b is formed at the inner edge of the elongated hole 15a formed in the thread guide member 15, the space for securing the blade and the member for securing the blade separately as in the prior art is secured So that the degree of freedom of design of the sewing machine is further improved.

Since the notch portion 15b does not require a mechanism for repeating contact and non-contact with the looper chamber L as in the prior art, the structure for cutting the looper chamber L is very simple, Not only the design of the sewing machine becomes easier, but also a sewing machine capable of cutting the looper chamber L when the looper chamber L is wound can be provided at a very low cost.

The yarn capturing member 20 is provided at a position between the outer periphery of the yarn catching member 14 and the lower shaft 2a from the outer periphery to the looper thread supply source side. That is, the end portion of the looper chamber L, which is distant from the side of the yarn control cam 14 on the supply source side of the looper chamber L, can be captured. The clearance 2b formed between the side of the thread control cam 14 on the supply source side of the looper chamber L and the bearing 4 of the lower shaft 2 provided on the side face side, It is possible to prevent the end portion L2 of the arm portion L from being wound. Therefore, the problem that the looper chamber L is very troublesome due to a large amount of the looper chamber L being wound around the gap 2b can be solved, and the reliability and comfort of the sewing machine can be greatly improved.

The notched portion 15b is a concave portion formed in the inner edge portion of the elongated hole portion 15a formed in the thread guide member 15 so that the wound looper chamber L can be cut without separately providing a blade or the like have. Therefore, it is not necessary to secure a space for fixing the blade and the member for fixing the blade separately as in the prior art, and the degree of freedom in designing the sewing machine is further improved. In addition, the actual thread cutting means can be provided without significantly changing the design of the conventional thread control apparatus. Therefore, the thread cutting means can be provided at a lower cost.

Since the notch 15b is threaded and cut, the inner edge of the notch 15b need not be cut. Therefore, the thread cutting means can be provided at a lower cost. Further, even if the inner edge portion of the notch portion 15b is not formed into a knife shape, it functions as a thread cutting means, but it is more preferable to process the inner edge portion of the notch portion 15b into a knife shape.

(Second Embodiment)

Next, a second embodiment will be described.

In the sewing machine provided with the yarn control device 10A, the end portion L1 of the looper chamber L formed by the looper side is wound around the shaft portion 2a between the yarn control cams 13 and 14 The notch 15b formed in the inner edge 15d of the lower portion of the elongated hole 15a of the thread guide member 15 is cut by the notch 15b, The thread path in the case where the looper thread supply side end portion L2 of the looper chamber L which has been cut off by the gap between the thread control cam 14 and the turning member 16 is the same as that of the first embodiment.

9 and 10, the actual control device 10A according to the second embodiment is provided with the thread control cam 14 (see Fig. 9) so as to extend along the axial direction from the side of the looper chamber supply side of the thread control cam 14 And a thread cutting scalpel 21 whose blade portion 21a is provided close to the outer peripheral portion of the cylindrical portion 14a.

The cylindrical portion 14a rotates in accordance with the rotation of the seal control cam 14 and is provided so as to insert the bearing 4 on the inner side (inner diameter side) of the cylindrical upper end portion. That is, the clearance 2b formed between the seal control cam 14 and the bearing 4 is covered by the cylindrical portion 14a. Therefore, the cylindrical portion 14a functions as a "first cylindrical portion ". Further, the bearing 4 functions as a "second cylindrical portion ".

As shown in Fig. 10, the yarn cutting scalpel 21 has a blade portion 21a arranged close to a circumferential outer circumferential portion of the cylindrical portion 14a. Further, the thread cutting scalpel 21 is fixedly supported on the sewing machine frame.

11, the looper thread supply side end portion L2 of the looper chamber L cut by the looper thread supply side end portion L1 or the notch portion 15b at the time when the looper chamber L has been cut off is also cut 8 (b), it may fall into a gap between the actual control cam 14 and the tiltable member 16. In this case, the end portion (L1 or L2) of the looper chamber L contacts the outer peripheral portion of the cylindrical portion 14a. At this time, if the thread control cam 14 rotates for reasons such as the sewing work by the sewing machine being continued, the looper chamber L is pulled by the rotation of the cylindrical portion 14a and wound around the cylindrical portion 14a.

The looper chamber L wound around the cylindrical portion 14a is wound around the circumferential outer circumferential portion of the cylindrical portion 14a as shown in Fig. 11, but the winding of the looper chamber L progresses, The looper chamber L wound with the thickness of the outer periphery of the cylindrical portion 14a is wound around the knife portion 21a of the thread cutting scalpel 21 And the looper chamber L is cut. Therefore, the thread cutting scalpel 21 functions as a "cutting member ".

Thereafter, the looper chamber L wound around the cylindrical portion 14a is removed with a tweezers or the like.

That is, when the sewing machine provided with the thread cutting apparatus 10A cuts the looper chamber L from the side closer to the looper than the thread control cam 13 during the sewing operation, the end L1 on the looper thread supply source side becomes 2 The notched portion 15b cuts the looper chamber L wound around the shaft portion 2a in the same manner as in the above-described embodiment. The end portion L2 of the end of the looper chamber L cut by the cutout 15b is separated from the clearance between the thread control cam 14 and the tiltable member 16 and the cylindrical portion 14a , The knife portion 21a of the thread cutting scalp 21 cuts the looper chamber L. As shown in Fig. The end portion L1 of the looper chamber L is removed by the thread control cam 14 without being wound around the shaft portion 2a so as to fall into the gap between the thread control cam 14 and the tilt member 16, The knife portion 21a of the thread cutting knife 21 cuts the looper chamber L even when it is wound around the portion 14a. This causes problems such as winding of a large amount of the looper chamber L on each portion of the lower shaft 2 where the looper chamber L such as the shaft portion 2a and the clearance 2b is likely to be wound up ≪ / RTI >

(Function and effect of the sewing machine according to the second embodiment)

According to the second embodiment, when the looper chamber L is separated from the gap between the actual control cam 14 and the pivoting member 16, the looper chamber L is wound around the outer peripheral portion of the cylindrical portion 14a. Further, the end portion of the cylindrical portion 14a on the looper chamber supply side is arranged so as to insert the bearing 4 inside thereof. That is, the clearance 2b between the side of the thread control cam 14 on the looper thread supply source side and the bearing 4 is located inside the cylindrical portion 14a. Thus, it is possible to prevent the end portion (L1 or L2) of the looper chamber (L) cut in the gap (2b) from being wound.

At this time, since the knurled portion 21a of the thread cutting scalpel 21 cuts the looper chamber L wound around the cylindrical portion 14a, the looper chamber L is wound around the outer periphery of the cylindrical portion 14a in a large amount Without cutting. This eliminates the problem that the looper chamber L is very troublesome to be removed due to the fact that the looper chamber L is wound around the gap 2b in a large amount when the looper chamber L is cut, Reliability and comfort are greatly improved.

(Etc)

12 is a side view showing the configuration of another embodiment of the thread guide member.

The thread cutting means in the above-described embodiment and the second embodiment is constituted by a notch 15b as a recess formed in the inner side edge portion of the thread guide member 15 on the lower side of the long hole 15a, , It is possible to use any mechanism that can cut and cut a looper chamber L that moves so as to be in sliding contact with the inner edge portion. For example, as shown in Fig. 12, it may be a convex portion 15Ab formed on the inner side edge portion of the lower shaft side of the elongated hole 15Aa of the thread guide member 15A. The configuration of the seal control device using the seal guide member 15A is the same as that of the seal control device 10 in the above-described embodiment except for the seal guide member 15A. The side of the side of the recess 15Ab on which the louper chamber L is fastened is formed so as not to slip out of the recess 15Ab before the loupe chamber L caught by the recess 15Ab is cut off. And the engagement portion 15Af formed by the inner edge portion 15Ad on the lower shaft side of the long hole portion 15a is greater than 0 degrees and not more than a right angle.

Also in this case, like the above-described embodiment, the convex portion 15Ab is a convex portion formed in the inner edge portion of the elongated hole portion 15Aa formed in the thread guide member 15A, so that no separate blade or the like is provided It is possible to cut the looper thread L which is wound without being caught. Therefore, it is not necessary to secure a space for fixing the blade and the member for fixing the separate blades as in the prior art, and the degree of freedom in designing the sewing machine is further improved. In addition, the actual thread cutting means can be provided without significantly changing the design of the conventional thread control apparatus. Therefore, the thread cutting means can be provided at a lower cost.

The inner peripheral portion of the notch portion 15b of the thread guide member 15 may be shaped like a knife. In this way, the looper chamber L caught by the notch 15b is more suitably cut.

The side portion of the concave portion 15Ab of the thread guide member 15A on the side where the looper chamber L is locked may be shaped like a knife. In this way, the looper chamber L caught by the retaining portion 15Af is more suitably cut. At this time, the inner side edge portion 15Ad on the lower shaft side near the latch fixing portion 15Af is formed into a knife shape along with the side portion of the concave portion 15Ab on which the looper chamber L is fastened, The looper chamber L can be cut.

The seal catching member does not necessarily have to be provided on the outer peripheral surface of the bearing 4 and the seal catching member is not necessarily provided on the outer peripheral surface of the bearing 4 so that the ends L1 and L2 of the looper chamber L do not fall into the clearance 2b. It may be in a position where the end portions L1 and L2 can be captured. For example, a seal catching member may be provided on the upper surface of the sewing machine frame fixed above the clearance 2b and always below the outer peripheral portion of the seal control cam 14. [

According to the embodiment described above, the yarn catching member 20 catches the cut ends L1 and L2 of the looper chamber L by the band-like bristle along the arc of the outer periphery of the bearing 4 So long as the seal catching member is capable of catching the end portion of the cut yarn. For example, the surface of the yarn capturing member may be a material having adhesiveness.

1 is a perspective view showing the construction of a yarn control device provided in a sewing machine according to the present invention.

2 is an explanatory view showing the positional relationship between the thread guide member and the lower shaft;

3 is a perspective view showing the actual control device when the large-diameter portion of the actual control cam is in contact with the looper chamber.

Fig. 4 is an explanatory view showing the path of the looper chamber at the inner edge portion of the long hole portion of the thread guide member, Fig. 4 (a) is an explanatory view showing the path of the looper chamber before passing over the notch, (b) is an explanatory view showing the path of the looper chamber when passing over the notch, and Fig. 4 (c) is an explanatory diagram showing the path of the looper chamber after passing over the notch.

Fig. 5 is an explanatory view showing displacement of the looper chamber when cutting of the looper chamber occurs, Fig. 5 (a) is an explanatory diagram showing a moment when the looper chamber is cut off from the louper side Fig. 5 (b) is an explanatory view showing the looper chamber removed by the actual control cam, and Fig. 5 (c) is an explanatory view showing a state in which the looper chamber is wound around the shaft portion between the two seal control cams.

Fig. 6 is an explanatory view showing the path of the looper chamber to the long hole portion of the thread guide member when the looper chamber is wound around the shaft portion between the two yarn control cams, Fig. 6 (a) Fig. 6 (b) is an explanatory view showing the path of the looper chamber before passing through the notch, Fig. 6 (c) is an explanatory view showing the path of the looper chamber before passing the notch, And Fig.

7 is a perspective view showing a yarn control device in which the turning portion is rotated upward.

8 (a) is an explanatory view showing a moment when the looper chamber is cut off by the notch, and Fig. 8 (b) is an explanatory view showing a path of the looper chamber side end portion of the looper chamber cut by the notch, Fig. 8 (c) is an explanatory view showing a state in which the end portion of the looper chamber is captured by the seal catching member. Fig.

Fig. 9 is an explanatory view showing a configuration of a yarn control device according to a second embodiment. Fig.

10 is an explanatory diagram of the configuration of the yarn control device according to the second embodiment as viewed from the direction along the lower shaft.

11 is an explanatory view showing a configuration in which a looper thread wound around a cylindrical portion is cut by a thread cutting scalpel.

12 is a side view showing a configuration of a thread guide member in another embodiment.

Fig. 13 is an explanatory view showing a state of a looper chamber in a conventional yarn control device. Fig. 13 (a) shows a state of a looper chamber at the time of normal sewing, and Fig. 13 And the looper thread is wound around.

Description of the Related Art [0002]

2: Lower shaft 3, 4: Bearing

5: thread path part 10: thread control device

11, 12: thread passing portion 13, 14: thread control cam

15: thread guide member 16:

20: yarn catching member

Claims (7)

A lower shaft rotated by rotation of the sewing machine motor, A looper swinging in conjunction with rotation of the lower shaft, Two thread passing portions, Two thread control cams provided on the lower shaft so as to be in sliding contact with the outer peripheral portion of the looper chamber disposed between the two thread passing portions and crossing the two thread passing portions, And a thread guide member which is provided between the two thread control cams and through which the looper thread slidingly contacts with the thread control cams is inserted and which has an elongated hole portion for reciprocating the looper thread in a predetermined direction, Wherein a thread tension is given to the looper chamber in accordance with a change in diameter of the two thread control cams, And the thread guide member includes thread cutting means provided in the middle of the inner edge portion on the lower shaft side along the longitudinal direction of the elongated hole portion to cut the looper thread. The method according to claim 1, Is fixed to the frame at a position between the actual control cam on the looper thread supply side and the looper thread supply source side from the outer periphery of the thread control cam to the lower shaft so that the end of the looper thread can be captured And a yarn catching member provided on the yarn catching member. The method according to claim 1, A first cylindrical portion provided on a side of a looper thread supply source side of the thread control cam and a cutting member disposed in the vicinity of the outer peripheral surface of the first cylindrical portion and capable of cutting the looper thread, Thread control device. The method of claim 3, And a second cylindrical portion fixed to the sewing machine frame for inserting the lower shaft is provided and one end of the second cylindrical portion is inserted into an end portion of the first cylindrical portion located on the looper chamber supply source side, And The method according to claim 1, Wherein the yarn cutting means is a yarn hooking portion for hanging the looper yarn in accordance with a change in diameter caused by rotation of the yarn count cam and for cutting the looper yarn in accordance with the change in the diameter. Control device. 6. The method of claim 5, Wherein the yarn cutting means is a concave portion formed in the inner side edge portion. 6. The method of claim 5, Wherein the yarn cutting means is a convex portion formed on the inner side edge portion.

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