JP2010069200A - Looper device of sewing machine for single chain stitch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a looper device of a sewing machine for single chain stitch capable of preventing breaking of thread and missing stitches even when a sewing machine needle oscillates when the needle pierces through a workpiece. <P>SOLUTION: The looper device of the sewing machine for single chain stitch includes: the sewing machine needle 3 moving vertically for piercing through the workpiece W wherein the thread is inserted to a needle tip 3a; and a vertically swinging looper 5 under the workpiece W for pulling in the thread of the sewing machine needle 3. In the looper device of the sewing machine for single chain stitch, stitches are formed by the sewing machine needle 3 and the vertically swinging looper 5 by using one thread. A jaw part 32 is provided with a regular passing point 30 of the needle tip of the vertically swinging looper 5. An inclined guide surface 33 declined toward the passing point 30 of the needle tip is formed on the upper face of the jaw part 32 in a position corresponding to a circumference of the passing point 30 of the needle tip so that the inclined guide surface 33 may guide the needle tip 3a of the sewing machine needle 3 to the passing point 30 of the needle tip. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a looper device for a single-ring stitch sewing machine.

  2. Description of the Related Art Conventionally, for example, a looper device for a single ring sewing machine for corrugated cardboard has a sewing needle passing through a workpiece on a needle plate by moving a thread through a needle tip and moving up and down, and a sewing needle thread under a needle plate. A vertical swing looper is provided, and a seam is formed by a single thread using the sewing needle and the looper (see, for example, Patent Document 1).

JP 2006-175157 A

  However, in the looper device for a single ring sewing machine, as shown in FIGS. 29 (a) and 29 (b), the cardboard whose sewing needle 3 is the workpiece W (two single cardboards in FIG. 29 (a)). 29 (b) shows a state in which two double cardboards are overlapped), and the sewing machine follows the shape of a relatively hard core Wa processed into a corrugated corrugated shape. The needle 3 may swing. When the sewing needle 3 is swung, the needle tip 3a touches the needle thread loop L forming a triangular space as shown in FIG. 29 (a), or thread breakage occurs, or the needle tip as shown in FIG. 29 (b). There is a problem in that 3a does not enter the needle thread loop L forming a triangular space and causes skipping. In FIGS. 29A and 29B, a line S indicates a needle position so that the sewing needle 3 can be properly dropped.

  Accordingly, the present invention has been made to solve such problems. By improving the shape of the looper, even if the sewing needle swings when the sewing needle penetrates the workpiece, thread breakage or skipping is caused. An object of the present invention is to provide a looper device for a single-ring stitch sewing machine that can prevent the above-mentioned problem.

The looper device for a single-ring stitching machine according to the present invention will be described with reference to the reference numerals attached to FIGS. 1 to 24 in order to facilitate understanding of the contents of the invention. A sewing needle (3) that passes through the sewing product (W) through the thread and moves up and down, and a vertical swing looper (5) that handles the thread of the sewing needle (3) below the sewing product (W). In a looper device for a single-ring stitch sewing machine in which a stitch is formed by a single thread by a sewing needle (3) and a vertical swing looper (5), a normal needle point passing point ( The needle tip (3a) of the sewing needle (3) is guided to the needle tip passage point (30) at a position corresponding to the periphery of the needle tip passage point (30) on the upper surface of the jaw portion (32) having 30). As described above, the inclined guide surface (33) descending toward the needle point passing point (30) is formed. Is shall.
According to the looper device having such a configuration, even if the sewing needle (3) swings when the sewing needle (3) penetrates the workpiece (W), the needle tip (3a) is moved by the inclined guide surface (33). The sewing needle (3) is straightly corrected by being guided and guided to the normal needle point passage point (30), so that the needle point (3a) touches the needle thread loop forming a triangular space or the needle thread loop. It is possible to reliably enter the normal needle position in the needle thread loop without entering the inside.

  In the looper device for a single-ring stitch machine according to claim 1, the shank (5b) of the longitudinal swing looper (5) is shaped like a flat plate having a square cross section and having a reamer hole (9). On the other hand, a shank fitting groove (11) and a reamer hole (12) capable of fitting the shank (5b) without gaps are formed in the looper base (8), and the shank (5b) is formed into the shank fitting groove (11). ), And the reamer bolt (14) is inserted into the reamer holes (9), (12) that are matched to each other by this fitting so that the reamer bolt (14) can be inserted / removed and fastened. It is possible to adopt a structure that is integrally attached to (). According to this, since the vertical swing looper (5) can be attached to the looper base (8) in a predetermined direction and at a predetermined height position, adjustment of the mounting height and angle of the vertical swing looper (5) is unnecessary. In addition, it is unnecessary to adjust the gap between the vertical swing looper (5) and the sewing needle (3). Furthermore, since the reamer bolt (14) can be inserted / removed by the reamer bolt (14) alone regardless of the swing stop position of the looper base (8), the vertical swing looper (5) can be easily attached and detached.

  According to the looper device for a single ring sewing machine of the present invention, even if the sewing needle swings when the sewing needle penetrates the workpiece, it can surely enter the normal needle position in the needle thread loop. There is an advantage that thread breakage and skipping can be prevented.

  Preferred embodiments of the present invention will be described below with reference to the drawings. 1 is an external perspective view of a single-ring stitch machine according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of a looper device of the single-ring stitch machine, FIG. 3 is a perspective view of the looper device, and FIG. FIG. 5 is a plan view of the looper device, FIG. 6 is a sectional view taken along line AA in FIG. 5, and FIG. 7 is an exploded perspective view of the looper of the looper device.

  In these drawings, a single ring sewing machine 1 according to an embodiment of the present invention includes a needle plate 2 provided on a sewing machine bed 1B by passing a thread (not shown) through a needle tip and moving up and down at the tip of a sewing machine arm 1A. The sewing needle 3 passing through the workpiece (cardboard or cloth, resin sheet, etc.) W (see FIGS. 29 (a) and 29 (b)) placed on the sewing needle 3, and the thread of the sewing needle 3 below the needle plate 2 In addition, a looper device 6 including a vertical swing looper 5 (see FIGS. 2, 3 and the like) that forms a seam with a single thread in cooperation with the sewing needle 3 is provided. The single-ring sewing machine 1 in the illustrated example is a cardboard sewing machine in which a seam is sewn to a stitched portion of a cardboard box.

  As shown in FIGS. 3 to 6, the looper device 6 includes a vertical swing looper 5 and a looper drive mechanism 7. As shown in FIGS. 7 to 14, the vertical swing looper 5 has a looper body 5 a and a shank 5 b provided at the base end of the looper body 5 a, and the shank 5 b is attached to the looper base 8. At the time of attachment, the shank 5b of the vertical swing looper 5 is formed in a flat plate shape having a square cross section, and a reamer hole 9 is provided at an intermediate portion of the shank 5b, and a notch 10 is provided at the tail end side end of the shank 5b. On the other hand, a shank fitting groove 11, a reamer hole 12, and a pin insertion hole 13 are formed in the looper base 8 so that the shank 5b can be fitted with no gap. Thus, the shank 5b of the vertical swing looper 5 is fitted into the shank fitting groove 11 without any gap, and the reamer bolt 14 is inserted into the reamer holes 12 and 9 that are matched with each other by this fitting, and the pin insertion hole 13 and the notch 10 are detented. 15 is passed from one side of the looper base 8 and the nut 16 is screwed into the screw 14a at the tip of the reamer bolt 14 protruding to the other side of the looper base 8 so that the vertical swing looper 5 is integrated with the looper base 8. Fasten and secure.

  As described above, the shank 5b of the vertical swing looper 5 is formed in a flat plate shape having a square cross section, and is fitted into the shank fitting groove 11 of the looper base 8 without a gap, and the reamer bolt 14 is inserted into the reamer holes 12 and 9 that match each other. By adopting an attachment structure in which the vertical swing looper 5 and the looper base 8 are integrated by fastening and fixing, the vertical swing looper 5 can be attached to the looper base 8 in a predetermined direction and at a predetermined height position. Therefore, it is not necessary to adjust the mounting height and angle of the vertical swing looper 5, and the gap g between the vertical swing looper 5 and the sewing needle 3 as shown in FIG. It is not necessary to adjust the gap g when passing through the punching portion 3b. Further, since the reamer bolt 14 can be inserted / removed by itself regardless of the position where the looper base 8 swings, the reamer bolt 14 can be easily attached without the necessity of adjusting the position of the looper base 8 when attaching / removing the vertical looper 5. It can be removed and is convenient for exchanging the vertical swing looper 5.

2 to 6, the looper driving mechanism 7 includes a lower shaft 20, a screw gear 21, a looper vibration source orthogonal shaft 22, a looper vibration source crank 23, a looper vibration source link 24, which are installed in the sewing machine bed 1B. The looper oscillating shaft 25, the looper oscillating lever 26, the looper oscillating rod 27, the looper shaft lever 28, the looper shaft 29, and the like. More specifically, the looper driving mechanism 7 receives the one-way rotation (arrow a in FIG. 3) of the lower shaft 20 and the lower shaft 20 via the screw gear 21 and rotates in one direction (arrow b in FIG. 3). A looper oscillating orthogonal shaft 22 and a looper oscillating lever 26 that rotates in one direction around the looper oscillating shaft 25 via a looper oscillating crank 23 and a looper oscillating link 24, A looper oscillating rod 27 that reciprocates back and forth with the reciprocating driving rotation of the looper oscillating lever 26, a looper shaft lever 28 that three members integrally reciprocate and rotate as the looper oscillating rod 27 moves back and forth, and a looper shaft 29, a looper base 8 integrally inserted and coupled to the looper shaft 29.
In this case, the vertical swing looper 5 is moved around the looper shaft 29 that is reciprocally driven and rotated by the looper driving mechanism 7 that operates in synchronization with the vertical reciprocating motion of the sewing needle 3, in the cloth feeding direction (sewing needle). Backward) Reciprocatingly swings over a predetermined back-and-forth swing range of Y (see FIG. 1).

Regarding the movement of the vertical looper 5, when the sewing product W is cardboard, the feed amount of the sewing product W is large, and the sewing product W is thick (about 16 mm for two cardboards), the stroke of the sewing needle 3 is The length becomes longer (50 mm in the embodiment), and the movement speed of the sewing needle 3 becomes faster. Therefore, as shown in FIG. 28 showing a comparison graph of the looper movement speed, in the looper movement by the general vertical looper mechanism, when the vertical looper scoops the needle thread, the movement of the vertical looper is delayed.
Therefore, the looper momentum (speed) from the bottom dead center to the squeeze position (position where the longitudinal swing looper scoops the needle thread) is increased as in the looper device of the embodiment shown in FIG.
Thus, by changing the movement curve of the vertical swing looper 5 from the bottom dead center to the squeeze position, the work W is corrugated and its feed amount is more than 10 mm. Even when two cardboards are as thick as about 16 mm, they can be sewn with stable tone.

  In the present invention, as shown in FIG. 20 to FIG. 24, the vertical swing looper 5 is lowered in a straight posture without a problem that the sewing needle 3 swings, and at the same time when the vertical swing looper 5 moves backward and swings, A regular needle point passing point 30 (see FIG. 22) through which the tip passes is provided on the upper surface of the jaw portion 32 provided with the punch 31 on the distal end side of the looper main body 5a. An inclined guide surface 33 is formed at a position corresponding to the periphery of the needle tip passing point 30 so as to slide the tip of the sewing needle 3 toward the needle tip passing point 30 and to guide the sewing needle 3 toward the needle tip passing point 30. It is.

  If the inclined guide surface 33 is formed on the vertical swing looper 5 as described above, when the sewing needle 3 penetrates the workpiece W, as shown in FIGS. 15 to 19, 29 (a) and 29 (b). Even if the sewing needle 3 swings and the needle tip 3a tries to pass an irregular needle tip passing point 34 as shown in FIG. 17, the needle tip 3a is Since the sewing needle 3 is straightened by being guided to the needle tip passing point 30, the needle thread loop L in which the needle tip 3a forms a triangular space as shown in FIGS. 29 (a) and 29 (b). It is possible to reliably enter the normal needle position in the needle thread loop L without touching or entering the needle thread loop L. Therefore, the needle tip 3a comes into contact with the needle thread loop L to cause a thread breakage, or the problem of causing skipping without entering the needle thread loop L has been solved.

1 is an external perspective view of a single ring stitch sewing machine according to an embodiment of the present invention. It is a disassembled perspective view of the looper device of the single ring sewing machine. It is a perspective view of the looper device. It is an external appearance perspective view which shows the assembly state of the looper apparatus. It is a top view of the looper device. It is the sectional view on the AA line in FIG. It is a disassembled perspective view of the looper of the looper apparatus. It is the external appearance perspective view which looked at the assembly state of the looper of the looper device from the left front. It is the external appearance perspective view which looked at the assembly state of the looper of the looper device from the right front. It is the external appearance perspective view which looked at the assembly state of the looper of the looper device from back. It is a front view which shows the assembly state of the looper of the looper apparatus. It is a top view which shows the assembly state of the looper of the looper apparatus. It is a right view which shows the assembly state of the looper of the looper apparatus. It is a rear view which shows the assembly state of the looper of the looper apparatus. It is a side view of a sewing needle and a looper before correction of a sewing needle of the looper device. It is a front view of a sewing needle and a looper before correction of a sewing needle of the looper device. It is the BB sectional view taken on the line in FIG. It is CC sectional view taken on the line in FIG. It is the DD sectional view taken on the line in FIG. It is a side view of a sewing needle and a looper after correction of a sewing needle of the looper device. It is a front view of a sewing needle and a looper after correction of a sewing needle of the looper device. It is the EE sectional view taken on the line in FIG. It is the FF sectional view taken on the line in FIG. It is the GG sectional view taken on the line in FIG. It is a rear view of the sewing machine needle and looper of the looper device. It is a side view of a sewing needle and a looper of the looper device. It is the HH sectional view taken on the line in FIG. It is a graph which compares and shows each looper movement speed by the looper apparatus of the Example of this invention, and a general vertical swing looper mechanism. When the sewing needle passes through the corrugated cardboard to be sewn, the troubled state diagram of the sewing needle swinging is shown, (a) shows the state where single cardboards are stacked, and (b) shows the double cardboards stacked. Indicates the state.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Single sewing machine 3 Sewing needle 5 Longitudinal looper 5a Looper main body 5b Shank 6 Looper device 8 Looper base 9,12 Reamer hole 11 Shank fitting groove 14 Reamer bolt 30 Needle point passage point 32 Jaw part 33 Inclined guide surface

Claims (2)

  The sewing machine includes a sewing needle that passes through the sewing product by passing the thread through the needle tip and moves up and down, and a vertical swing looper that pulls the thread of the sewing needle below the sewing product. In a looper device of a single-ring stitch machine that forms a seam with a book thread, a position corresponding to the periphery of the needle point passing point on the upper surface of a jaw portion having a normal needle point passing point of the longitudinal looper Further, an inclined guide surface that is lowered toward the needle point passing point is formed so as to guide the needle point of the sewing needle to the needle point passing point.   The shank of the vertical swing looper is formed in a flat plate shape having a square cross section and a shape having a reamer hole, while a shank fitting groove and a reamer hole are formed on the looper base so that the shank can be fitted without a gap. Are fitted in the shank fitting groove, and the vertical swing looper is integrally attached to the looper base by inserting and fastening a reamer bolt to the reamer holes that match each other by this fitting. A looper device for a single ring stitch sewing machine according to claim 1.

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