JPH0727016Y2 - Double chain stitch sewing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a double needle having a needle that is moved up and down and a looper that cooperates with the needle to form a double chain stitch on a work cloth. Concerning chain stitch sewing machines.

(Prior Art) In a conventional double chain stitch sewing machine, when a double chain stitch seam is formed, the looper is moved in the axial direction of the looper shaft with the rotation of the moving eccentric ring on the lower shaft, With the rotation of the swinging eccentric on the lower shaft, the looper is reciprocally swung around the looper axis, so that the looper is moved along an elliptical locus, and the looper and needle cooperate to form a work cloth. A double chain stitch is formed, and the feed dog of the cloth feed mechanism connected to the lower shaft imparts a feed motion to the work cloth.

(Problems to be solved by the invention) However, in the conventional sewing machine, the power transmission mechanism for reciprocating the looper in the axial direction of the looper shaft and the power transmission mechanism for swinging the looper have a lower shaft and a looper. Since they are installed independently of each other, the mechanism becomes complicated, the number of parts increases, assembly becomes troublesome, the manufacturing cost rises, and the sewing machine becomes larger. There's a problem.

(Object of the Invention) The present invention was made in order to solve the above problems, and its purpose is to make the looper reciprocate in the axial direction of the looper shaft with the rotation of the lower shaft and shake the looper. In order to move the sewing machine, it is not necessary to provide an independent power transmission mechanism between the two, and the structure can be simplified and the number of parts can be reduced, whereby the entire sewing machine can be downsized and can be manufactured at low cost. To provide a simple double chainstitch sewing machine.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, a lower shaft rotatably supported around an axis and a first eccentric ring mounted on the lower shaft. , A swing link 31 and a horizontal feed link 35 that are connected to the first eccentric ring 29 and that impart a horizontal feed motion to the feed dog 32 by rotation of the first eccentric ring 29, and are substantially orthogonal to the lower shaft. A looper shaft, which is arranged so as to be swingable around an axis and is movable in the axial direction, is connected to the looper, and is attached to the lower shaft, and the looper shaft is attached as the lower shaft rotates. And a second eccentric wheel for imparting a swinging motion to the swinging link, further comprising a square piece on the swinging link, and a connecting body having a sliding groove formed in the looper shaft and opening in a direction orthogonal to the axis of the looper shaft. The swing link is provided by arranging a square piece in the sliding groove of the connected body. The looper shaft with the swing in the axial direction so as to reciprocate.

(Operation) Therefore, according to the present invention, when the lower shaft is rotated, the swing link and the horizontal feed link are actuated via the first eccentric ring mounted on the lower shaft, and the feed dog is horizontally moved. And the swinging motion is imparted to the looper shaft and the looper via the second eccentric ring attached to the lower shaft. On the other hand, the square piece provided on the swing link is provided in the slide groove of the connecting body provided on the looper shaft, and the swing link for swinging the feed dog for the horizontal feed motion is moved along with the swing piece. The looper shaft is reciprocated in the axial direction.

Embodiment An embodiment embodying the present invention will be described in detail below with reference to the drawings. As shown in FIG. 1, the needle 1 is attached to the lower end of the arm 11a of the frame 11 made of a metal material.
2a, the needle bar 12 having a needle bar hanger 15 fixed in the middle is vertically movably supported, the driven pulley 13a is provided at the right end, and the upper shaft 13 having the crank 14 at the left end is provided to the left and right. The rotation of the upper shaft 13 is rotatably supported around the extending axis, and the rotation of the upper shaft 13 is transmitted to the needle bar 12 through the engagement between the crank pin 14a on the crank 14 and the guide groove 15a of the needle bar holder 15 and the needle bar 12 Is moved up and down.

As shown in FIG. 1, a lower shaft 23 extending in parallel with the upper shaft 13 is rotatably supported in a bed portion 11b of a frame 11, and a pair of transmission pulleys 24, 25 of a large size and a small size are integrally rotated at the right end thereof. It is installed as possible. Then, the power of the drive motor (not shown) is transmitted to the lower shaft 23 via the large transmission pulley 24 and is transmitted to the upper shaft 13 via the small transmission pulley 25, the belt 26 and the driven pulley 13a. The shafts 23 and 13 are rotated synchronously.

As shown in FIGS. 1 and 4, a first eccentric ring 29 is integrally rotatably mounted on the left end of the lower shaft 23, and the first eccentric ring 29 is placed in the bed portion 11b close to the first eccentric ring 29. A swing link 31 that is swingable is provided around the support shaft 30. At the upper end of the swing link 31, a feed bar 33 having a feed dog 32 mounted is rotatably connected at its base end, and a tip fork portion 34 of the feed bar 33 is attached to the outer periphery of the first eccentric ring 29. Engaged. The horizontal feed link 35 is externally fitted to the first eccentric ring 29 at one end, and is rotatably connected to the intermediate portion of the swing link 31 at the other end. Then, with the rotation of the first eccentric wheel 29, vertical feed is applied to the feed dog 32 via the forked portion 34 of the feed base 33, and the needle plate 36 on the frame 11 is projected and retracted on the upper surface. , The horizontal feed link 35, the swing link 31, and the feed table 33 are used to feed the feed dog 32 in the horizontal direction, and as a result, the feed dog 32 is given a four-motion feed along a known rectangular locus. To be done. In this embodiment, the first eccentric ring 29,
Horizontal feed link 35, swing link 31, feed table 33 and feed dog
The cloth feeding mechanism F is constituted by 32.

As shown in FIGS. 1 and 2, a looper shaft 45 extending in a direction orthogonal to the lower shaft 23 is swingable in the pair of support pieces 41, 42 provided in the bed portion 11b and is axially movable. A looper 46 is movably inserted and supported, and a looper 46 is fixed to the front end of the looper shaft 45 at the base end thereof so as to be positioned below the needle bar 12.

Further, as shown in FIGS. 2 and 5, the looper shaft 45
A swing arm 47 having an inverted U-shape is supported at its base end so as to be swingable integrally with the middle portion of the, and as shown in FIG.
The bed portion 11b is provided between the lower shaft 23 and the looper shaft 45.
A swing arm 48 is swingably supported at its base end. A connecting link 49 is disposed between the tip ends of the swing arm 47 and the swing arm 48, and the connecting link 49 operatively connects the two. On the other hand, as shown in FIGS. 1, 4 and 6, a second eccentric wheel 50 for swinging the looper shaft 45 is integrally rotatably mounted on the intermediate portion of the lower shaft 23. An operating arm 51 that is moved up and down as the eccentric wheel 50 rotates is attached to the outer periphery of the eccentric portion. An H-shaped link 52 is provided between the lower end of the operating arm 51 and the intermediate portion of the swing arm 48, and a gap is formed between both side surfaces of the swing arm 48 and the link 52. In this state, both 51 and 48 are operatively connected by this link 52.

Then, as the second eccentric wheel 50 rotates, the swing arm 48 reciprocally swings via the operating arm 51 and the link 52, and the looper via the swing arm 48, the connecting link 49 and the swing arm 47. The shaft 45 and the looper 46 are integrally reciprocally rocked. The movement of the operating arm 51 in the front-rear direction caused by the rotation of the second eccentric wheel 50 is not transmitted to the swing arm 48 because there is a gap between the link 52 and the swing arm 48. .

As shown in FIG. 2, FIG. 3 and FIG. 5, a connector 5 having a sliding groove 53a extending vertically at the rear end of the looper shaft 45.
3 is fixed, and a square piece 54 protruding from the lower part of the swing link 31 is slidably disposed in the sliding groove 53a,
The swing link 31 is connected to the looper shaft 45 by both 53 and 54. Then, with the rotation of the first eccentric ring 29,
Horizontal feed link 35, swing link 31, square piece 54, and connecting body 53
The looper shaft 45 and the looper 46 are reciprocally moved in the axial direction via the. As a result, the looper 46 is swung so as to draw an elliptical locus across the vertical movement locus of the needle 12a.
A power transmission mechanism T is composed of the square piece 54 and the connecting body 53.

The frame 11 in this embodiment is covered with a synthetic resin cover 55 having a gripping opening 55a as shown by the chain double-dashed line in FIG.

Now, in the double chainstitch sewing machine configured as described above, when the power of the drive motor (not shown) is transmitted to the pair of large and small transmission pulleys 24, 25, the small transmission pulley 25, the belt 26 and the driven pulley 13a. The upper shaft 13 is rotated via. With the rotation of the upper shaft 13, the needle bar 12 is vertically moved through the crank 14 and the needle bar holder 15, and the needle 12a is vertically moved through the needle plate 36.

Further, the lower shaft 23 and the first and second eccentric wheels 29, 50 are integrally rotated in synchronization with the upper shaft 13 via the large transmission pulley 24, and the operating arm is rotated as the second eccentric wheel 50 rotates. The looper shaft 45 via the 51, the link 52, the swing arm 48, the connecting link 49 and the swing arm 47.
And the looper 46 is reciprocally swung about the axis of the looper shaft 45. Further, with the rotation of the first eccentric wheel 29, the looper shaft 45 is reciprocally moved in the axial direction via the horizontal feed link 35, the feed base 33, the swing link 31, the square piece 54 and the connecting body 53, and As a result, the looper 46 is swung along the elliptical locus. Then, based on the operation of the looper 46 and the needle 12a, the two threads respectively carried by them cause
Double chain stitches are formed on a work cloth (not shown) on the needle plate 36.

Also, with the rotation of the first eccentric wheel 29, a horizontal feed link
A four-movement feed is imparted to the feed dog 32 through the 35, the swinging link 31 and the feed base 33, and the feed dog 32 and the presser foot shown in FIG.
A work cloth (not shown) is transferred onto the needle plate 36 in the cloth feed direction in cooperation with 56.

As described above, in this embodiment, by connecting the swinging link 31 and the looper shaft 45, which are swung to give the feed dog 32 a horizontal feed motion, by the connecting body 53 and the square piece 54. Since the power for reciprocating the looper shaft 45 in the axial direction is obtained from the cloth feeding mechanism F, only for reciprocating the looper shaft 45 in the axial direction,
It is not necessary to provide a special power transmission mechanism between the lower shaft 23 and the looper shaft 45. Therefore, the number of parts constituting the transmission mechanism can be reduced and the structure can be simplified and the entire sewing machine can be downsized. In addition, it can be manufactured at low cost.

(Effects of the Invention) As described in detail above, the present invention is constructed by connecting the swinging link and the looper shaft, which are swung to impart a horizontal feed motion to the feed dog, by a connecting body and a square piece. Since the power is obtained from the drive mechanism side of the feed dog to reciprocate the looper shaft in the axial direction, the lower shaft and the lower shaft are moved to reciprocate the looper in the axial direction of the looper shaft and swing the looper. It is not necessary to provide an independent power transmission mechanism between the looper and the looper, and only the first and second eccentric wheels need to be attached to the lower shaft to operate the looper and the feed dog. The number of parts is reduced, and as a result, the sewing machine as a whole can be downsized and can be manufactured at low cost, which is an excellent effect.

[Brief description of drawings]

FIG. 1 is a front view of a double chainstitch sewing machine embodying the present invention, FIG. 2 is a partially enlarged left side view, FIG. 3 is a partially enlarged rear view, and FIG. 4 is a perspective view showing a cloth feeding mechanism and the like. 5 is a perspective view showing the looper actuating mechanism, and FIG. 6 is a partially enlarged sectional view showing the second eccentric wheel. 12a ... Needle, 23 ... Lower shaft, 29 ... First eccentric wheel, 31 ... Oscillating link, 32 ... Feed dog, 33 ... Feeding base, 35 ... Horizontal feed link, F ... Cloth Feed mechanism, 45 …… Rooper shaft, 46
...... Looper, 50 …… Second eccentric wheel, 53 …… Coupling, 54…
… Square piece, T …… Power transmission mechanism.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Takeo Ueno Creator Keno Ueno 1040, Terakawato-cho, Mizunami-shi, Gifu Mizunami Seiki Co., Ltd. (56) References: 621-243483 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A needle (12a) which is moved up and down and the needle (12a).
A double chainstitch sewing machine including a looper (46) that cooperates with the work cloth to form a double chainstitch stitch, and a lower shaft (23) rotatably supported about an axis; The first eccentric ring (29) mounted on the lower shaft (23) is connected to the first eccentric ring (29), and the first eccentric ring (29) rotates to feed the feed dog (32) in the horizontal direction. A swing link (31) and a horizontal feed link (35) for imparting a feed motion, and a swing link (31) and a horizontal feed link (35) that are swingably arranged around an axis substantially orthogonal to the lower shaft (23) and can move in the axial direction. Is installed in
A looper shaft (45) to which the looper (46) is connected; and a looper shaft (45) which is attached to the lower shaft (23) and imparts a swinging motion to the looper shaft (45) as the lower shaft (23) rotates. A sliding groove (53a) which is provided with two eccentric wheels (50), and further provided with a square piece (54) on the swing link (31), and which opens on the looper shaft (45) in a direction orthogonal to its axis. And a square piece (54) is provided in a sliding groove (53a) of the connecting body (53), and the looper shaft is moved along with the swing of the swing link (31). A double chain stitch sewing machine characterized in that (45) is reciprocally moved in the axial direction.