JPH11216286A - Lock sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To impart tension to a looper thread by a simple structure. SOLUTION: Relating to this lock sewing machine, a ring looper 13 captures the loop of a needle thread mounted to a needle 19 when the needle 19 is elevated, the needle 19 captures a ring looper thread 20 mounted to the ring looper 13 when the needle 19 is lowered and thus, stitch is formed. In this case, an upper shaft link mounted to a main shaft so as to drive an upper shaft is provided with an auxiliary needle thread take-up 7 and the tension is imparted to the ring looper thread 20 by the auxiliary needle thread take-up 7 after the lowering start of the needle 19 until the capture end of the ring looper thread 20 of the needle 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock sewing machine, and more particularly to an auxiliary balance device for a lock sewing machine.

[0002]

2. Description of the Related Art In a lock sewing machine, as is well known, a ring looper captures a loop of a needle thread mounted on the needle when the needle is raised, and the needle is mounted on the ring looper when the needle is lowered. A seam is formed by catching the formed looper thread. Thus, in such a lock sewing machine, from the start of the lowering of the needle to the time when the needle catches the annular looper thread mounted on the annular looper, the ring looper thread becomes thickened, causing There was a fear that the mounted needle could not catch the looper thread. Therefore, for example, Japanese Patent Application Laid-Open
In the lock sewing machine disclosed in JP-A-31760, tension is applied by scooping up the ring looper thread by the lever at the above-mentioned time.

[0003]

However, in this device, a separate transmission mechanism must be provided between the main shaft and the shaft on which the lever is mounted in order to drive the lever.
The structure of the lock sewing machine was further complicated.

[0004] Therefore, an object of the present invention is to provide a lock sewing machine in which such a problem is eliminated.

[0005]

Means for Solving the Problems In order to solve the above technical problem, a technical means (first configuration) taken in claim 1 is that a ring looper is mounted on the needle when the needle is raised. An upper shaft is driven in a lock sewing machine in which a loop of a needle thread is captured, and when the needle is lowered, the needle captures a loop looper thread mounted on the loop looper to form a seam. An auxiliary balance is provided on the upper shaft link mounted on the main shaft so as to apply tension to the annular looper thread by using the auxiliary balance from the start of the lowering of the needle to the completion of the capture of the annular looper thread of the needle. That is, a lock sewing machine is constructed.

In order to solve the above technical problem, a technical measure (second configuration) taken in claim 2 is that a ring looper catches a loop of a needle thread mounted on the needle when the needle is raised. In the lock sewing machine, when the needle descends, the needle catches a loop looper thread mounted on the loop looper to form a seam, and is connected to a loop looper base for fixing the loop looper. A thread take-up spring is provided on the completed ring looper balance, the ring looper thread reaches the ring looper via the ring looper balance and the thread take-up spring, and the capture of the ring looper thread of the needle from the start of the needle lowering is completed. In the meantime, a lock sewing machine is configured such that the thread take-up spring applies tension to the ring looper thread.

[0007]

[Operation and Effect] The operation and effect of the first configuration are as follows. That is, since the upper shaft link mounted on the main shaft to drive the upper shaft is an existing component of the lock sewing machine, the tension can be applied to the ring looper thread simply by attaching an auxiliary balance to the upper shaft link. Thus, there is no need to provide a special mechanism for driving the lever of the auxiliary balance as in the conventional case.

The operation and effect of the second configuration are as follows. That is, the ring looper balance connected to the ring looper base for fixing the ring looper is an existing component of the lock sewing machine. Thus, there is no need to provide a special mechanism for driving the lever of the auxiliary balance as in the conventional case.

[0009]

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

1 to 3, a main shaft 2 is rotatably supported on an arm 1 of a lock sewing machine. A needle bar driving cam 3 is eccentrically fixed on the main shaft 2. The lower portion of the upper shaft link 4 is mounted on the needle bar drive cam 3. The upper portion of the upper shaft link 4 is pivotally supported by a balancer 6 that rotates integrally with the upper shaft 5. Thus, the reciprocating vertical movement of the upper shaft link 4 accompanying the integral rotation of the main shaft 2 and the needle bar drive cam 3 causes the balancer 6 and the upper shaft 5 to rotate integrally. An auxiliary balance 7 for flat stitching is fixed to the lower portion of the upper shaft link 4 with a screw 8, and the auxiliary balance 7 also swings in synchronization with the main shaft 2. .

A loop looper thread 20 fed from a thread spool (not shown) is supplied to a loop looper 13 through a thread tension adjusting device 10, a pair of thread guides 9, a thread guide 28 and a loop looper balance 14 in the arm 1. . The ring looper 13 and the ring looper balance 14 are fixed to a ring looper base 12 fixed on a ring looper shaft 11 rotatably supported by the arm 1 via screws 17 and screws 18, respectively. The looper shaft 11 is arranged at right angles to the main shaft 2 in the arm 1 and is linked to the main shaft 2 via a gear mechanism (not shown). Then, while the main shaft 2 makes one rotation, the ring looper shaft 11, the ring looper base 12, the ring looper 13, and the ring looper balance 14 swing integrally within a predetermined angle range (between AB). Has become.

When performing the flat stitching by rotating the main shaft 2 once, the loop looper 13 swings rightward from the left dead center A to the right dead center B in FIG.
9 begins to descend from the upper position. Then, as shown in FIGS. 4 and 5, the needle 19 for the flat stitch is connected to the looper thread 20.
When passing between the loop looper 13 and the loop looper 13, the needle thread mounted on the needle 19 catches the loop looper thread 20 to form a flat stitch.

The loop looper 13 reaches the left dead center A, and starts swinging from the left dead center A to the right dead center B again. Until the ring looper thread 20 passes, tarmi is generated (FIG. 6). This tarmi may cause a catch failure of the flatbed needle 19, but the loop looper thread 20 is attached to the auxiliary balance 7.
In addition, since tension is applied to the ring looper thread 20 by the pair of thread guides 9, it is possible to prevent the ring looper thread 20 from being thickened. That is, the auxiliary balance 7
Swings in synchronism with the main shaft 2, from when the ring looper 13 starts swinging in the direction from the left dead center A to the right dead center B until the needle 19 for flat stitching passes through the loop looper thread 20. Since a predetermined tension is applied to the ring looper thread 20 by the auxiliary balance 7 under such movement,
It is possible to prevent the ring looper yarn 20 from being thickened.

The pair of thread guides 9 is not always necessary.

FIGS. 7 and 8 show modifications of the lock sewing machine described above. In the lock sewing machine according to this modification, a thread take-up spring 38 for applying further tension to the ring looper thread 20 is provided on the ring looper balance 14 of the lock sewing machine described above. That is, the ring looper base 1 to which the ring looper 13 is fixed.
2, a first part 14a and a second part 14b of the ring looper balance 14 are fixed by stepped pins 39. The stepped pin 39 is formed of a large-diameter first portion 39a, a medium-diameter second portion 39b, and a small-diameter third portion 39c, and the small-diameter portion 39c of the stepped pin 39 is screwed to the ring looper base 12. When the first part 14a and the second part 14b of the ring looper balance 14 are fixed to the ring looper base 12, the second part 39b and the first part 39a of the stepped pin 39 are connected to the second part of the ring looper balance 14. It has a form projecting from the portion 14b.

The second portion 39b of the stepped pin 39
A thread take-up spring 38 is mounted on the upper end of the thread take-up spring 38.
8a is a hole 3 formed in the first portion 39a of the stepped pin 39.
9d is inserted and locked. And the thread take-up spring 38
Is formed in a hook shape, and reaches the annular looper 13 through a guide groove 14d formed in the first portion 14a of the annular looper balance 14 and a guide groove 14e formed in the second portion 14b. A tension is applied to the looper thread 19.

The loop looper thread 20 formed by the thread take-up spring 38
The tension is applied to the loop looper yarn 20 by the auxiliary balance 7 in synchronization with the tension application. In other words, the auxiliary balance 7 is responsible for feeding out the loop looper thread 20 from the thread spool and applying tension to the loop looper thread 20.
In view of the arrangement position, there is a possibility that the latter cannot be fulfilled, and the tension is applied to the ring looper thread 20 by the thread take-up spring 38 to the ring looper thread 20 by the auxiliary balance 7 so as not to cause such a situation. To compensate for the lack of tension application.

[Brief description of the drawings]

FIG. 1 is a front view showing a thread supply path in a lock sewing machine according to an embodiment of the present invention.

FIG. 2 is a perspective view of an auxiliary balance device according to an embodiment of the present invention.

FIG. 3 is a diagram showing an operation mode of the auxiliary balance device according to one embodiment of the present invention.

FIG. 4 is a diagram illustrating the capture of a ring looper yarn by a needle.

FIG. 5 is a diagram illustrating the completion of the capture of the loop looper thread by the needle.

FIG. 6 is a graph showing the relationship between the thread feeding / thickness amount and the position of the needle.

FIG. 7 is a front view showing the vicinity of a ring looper table on which a thread take-up spring is mounted.

FIG. 8 is an exploded perspective view of the ring looper balance shown in FIG. 7;

[Explanation of symbols]

 2: Main shaft 4: Upper shaft link 5: Upper shaft 7: Auxiliary balance 13: Loop looper 14: Loop looper base 19: Needle 20: Loop looper thread 38: Thread take-up spring 39: Stepped pin

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kenji Yoshida 2-1-1 Asahi-cho, Kariya-shi, Aichi, Japan Aisin Seiki Co., Ltd.

Claims (2)

[Claims] 1. A loop looper captures a loop of a needle thread mounted on the needle when the needle is raised, and the needle captures a loop looper thread mounted on the loop looper when the needle is lowered. In the lock sewing machine in which the seam is formed by the above, an auxiliary balance is provided on the upper shaft link mounted on the main shaft to drive the upper shaft, and the needle of the ring looper thread is captured from the start of the lowering of the needle. A lock sewing machine wherein the auxiliary balance is used to apply tension to the ring looper thread until completion. 2. A loop looper captures a loop of a needle thread mounted on the needle when the needle is raised, and the needle captures a loop looper thread mounted on the loop looper when the needle is lowered. In a lock sewing machine in which a seam is formed by the above, a thread take-up spring is provided on a ring looper balance connected to a ring looper base for fixing the ring looper, and the ring looper thread is passed through the ring looper balance and the thread take-up spring. A lock sewing machine that causes the thread take-up spring to apply tension to the ring looper thread from the start of the lowering of the needle to the completion of the capture of the loop looper thread by the needle. .