JPH0312913B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The invention of this application relates to a crochet opening/closing mechanism for a sewing machine. More specifically, the present invention relates to a crochet opening/closing mechanism in which a hook-shaped portion for pulling up the sewing thread of a sewing machine can be opened and closed.

Traditionally, in single-ring stitching machines, when a looper is operated to form a loop with sewing thread from a thread winding device installed below the sewing machine table, the crochet hook that passes through and descends through the fabric attached to the stitching frame catches this loop. and rise again in the dough,
A single chain stitch is formed on the fabric. Since the fabric mounted on the embroidery frame moves in a desired direction around the support shaft, a desired embroidery stitch is formed on the fabric mounted on the embroidery frame in accordance with the positional movement. When the crochet needle moves up along with the sewing thread in the fabric where the embroidery stitches are to be made, the weaving threads that make up the fabric are often pulled up inadvertently, resulting in a defect in which beautiful embroidery stitches cannot be formed. This phenomenon often occurs when sewing special woven fabrics such as pile. Embroidery products in which the weaving threads are carelessly pulled up onto the surface of the fabric in this way are treated as defective products, resulting in large economic losses.

Therefore, the inventor of the present application devised a new crochet opening/closing mechanism to overcome the above-mentioned defects, and an outline thereof will be described below. In other words, when the crochet hook catches the loop formed by the looper located below the fabric and moves up in the fabric, the protrusion of the curved gouge part of the crochet hook does not pull the weaving thread of the fabric and move upward with it. In addition, the curved gouge part is closed by a guide piece of the needle that slides up and down a slide groove provided in the crochet main body, so that a single sewing thread held by the curved gouge part can smoothly pass through and rise inside the fabric. be.

An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 2 is a sectional view illustrating main related members according to the present invention.

The present invention is roughly divided into the following four devices. That is, the needle bar and slide piece vertical drive device a, the needle bar and slide piece drive rod rotation device b, the nipple drive device c, and the presser foot drive device d.

First, the needle bar and slide piece vertical drive device a will be described. On the outer periphery of the needle bar 2 of the drive device a, an outer peripheral cylinder 22, which will be described later, is provided so as to be vertically slidable and rotatable together with the needle bar 2. Further, a slide piece drive rod 4 is provided inside thereof so as to be slidable up and down. A crochet hook N according to the present invention is fixed 6 to the lower end of the needle bar 2. As shown in FIG. 3, the crochet hook N has a curved hollow portion R at its end, and a vertical groove S is provided in a vertical groove 10 bored in the side surface of the main body 8.

A circular groove 12 is provided at the upper end of the slide piece drive rod 4.
An annular lifting ring 14 is provided, and a first annular ring 30, which will be described later, is attached to this annular lifting ring.
A vertical groove 16 is provided on the side surface of the slide piece drive rod 4 near the annular lifting ring 14, and the end of a nut 18 fixed to the needle bar 2 is slidably engaged in this groove. Furthermore, a cavity 20 is provided between the lower end of the slide piece drive rod 4 and the needle bar 2. Therefore, the slide piece drive rod 4 is made vertically movable within the needle bar 2 in the longitudinal direction of the vertical groove 16 and the cavity 20. An outer cylinder 22 is fixed to the outer periphery of the needle bar 2 with screws 24 . Another circular groove 2 is formed on the outer periphery of the outer cylinder 22.
5 is drilled, and another second annular ring 44 fits into this groove. Regarding the slide piece vertical movement device, a lifting ring 14 is attached to the slide piece drive rod 4 side of the slide piece drive member 28 which is slidably attached to one end of the vertical shaft 26 provided parallel to the needle bar 2. circular groove 1
A first annular ring 30 that fits into the slide piece drive member 28 is fitted into a cam groove 36 of a first eccentric cam 36 which has a rotatable shaft 34 supported by a bearing 32 on the other side of the slide piece drive member 28. A movable roller or projection 40 is provided. Next, regarding the needle bar vertical drive device, an outer cylinder 22 is attached to one side of the needle bar drive member 42 which is slidably fitted to the lower end of the vertical shaft 26.
The second annular ring 44 is fitted into the annular ring 25 of the second eccentric cam 50, and the second eccentric cam 50 is fitted into the cam groove 52 of the second eccentric cam 50, which has a rotatable shaft 48 supported by a bearing 46 on the other side. Slidable roller (or protrusion) 5
4 will be provided. The distance of the cam groove 38 formed in the first eccentric cam 36 from the center of the eccentric cam is smaller than the distance of the cam groove 52 of the second eccentric cam 50 from the center of the eccentric cam.

Next, the needle bar and slide piece drive rod rotating device b will be explained. An umbrella gear 58 supported by two pairs of bearings 56 is fixed to the outer periphery of the outer cylinder 22, and an umbrella gear 64 meshes with the shaft 62 which is rotatably and horizontally supported by another bearing 60. will be established. Therefore, shaft 6
2 rotates in a predetermined direction, this movement is caused by the bevel gear 6
4. The outer cylinder 22 of the needle bar 2 rotates through the bevel gear 58, and the needle bar 2 and the slide piece drive rod 4 attached to the needle bar 2 by the nut 18 also rotate, so the crochet needle N also rotates. Of course it is possible. Next, the nipple drive device c will be explained. A nipple 70 having a hole 68 through which a crochet needle N can be inserted is fixed to the lower end of a nipple cylinder 66 which fits around the outer periphery of the needle bar 2 and is slidable. A circular groove 72 is bored in the upper end of the nipple cylinder 66. A protrusion 80 (or roller) of a nipple drive member 76 with a U-shaped section 78 mounted on a second longitudinal shaft 74 is connected to a third eccentric cam 86 with a rotating shaft 84 supported on a bearing 82.
It is slidably fitted into a cam groove 88 bored in the cam groove 88 . Inside the U-shaped portion 78, the second vertical shaft 7 is in contact with a coil spring 90 wound around the second vertical shaft 74.
4 includes a third annular ring 9 that fits into the circular groove 72;
Attach 2. During operation of the nipple drive device, the nipple 70 moves up and down due to the elastic action of the coil spring 90. Reference numeral 94 denotes a support frame, which is located on the outer periphery of the nipple cylinder 66 and supports the needle bar 2, slide piece drive rod 4, and nipple cylinder 66 according to the present invention.
etc.

Although the presser drive device d is not directly related to the present invention, its outline will be explained. The presser 95 is connected to a vertical rod 96, a vertical shaft 98, a cam drive mechanism 100, etc., and by the operation of the cam drive mechanism 100, the presser 95 presses and releases the embroidery fabric W with appropriate pressure. . In particular, due to the elastic operation of the spring mechanism 102 attached to the end of the vertical rod 96, the vertical pressing movement of the presser 95 is smoothly performed according to the condition of the fabric W to be embroidered.

Further, the embroidery fabric W is placed on the table T while being held between the inner frame 104 and the outer frame 106. The crochet needle N is connected to the fabric W and the hole 109 of the needle plate 108
Looper 1 for stabbing is inserted and lowered.
Sewing thread 114 is supplied to thread 10 from thread spool 112.
is captured by the curved gouge R, and then raised, and together with the slide piece S, penetrates through the fabric W to form a single-ring stitch in the fabric W. At that time, when the crochet needle N is in a higher position than the fabric W, the stitching frame 10
A movable support frame 116 for the embroidery frame provided below 4, 106 operates and moves the fabric W in a desired direction together with the embroidery frame, thereby forming various embroidery stitches. Although the needle bar, the slide piece drive rod rotating device b, and the movable support frame 116 are not shown, they are electrically and mechanically interlocked so that the curved gouge portion R of the crochet needle N can always capture the sewing thread 114 correctly. It works, but I will omit the details.

Next, the operational relationship between the main body 8 of the crochet hook N and the slide piece S according to the present invention will be explained. 1 and 2 clearly show the operational relationship between the two members, that is, the crochet main body 8 and its slide piece S. It is inserted and lowered, and the sewing thread 114 is captured by the gouged portion R. In the case of FIG. 1A and FIG. The same holds true for the relationship between the needle bar 2 and the second eccentric cam 50 located at the lower level, and the hollowed out portion R of the crochet hook N is in an open state. The details will be described later based on FIG.

Now, due to the rotation of the shaft 34, the first eccentric cam 36
is activated to move the first vertical shaft 26 and the slide piece drive member 2.
8. Slide piece drive rod 4 via first annular ring 30
and the slide piece S moves, and at the same time the shaft 48
The second eccentric cam 50 is activated by the rotation of the first eccentric cam 50.
The needle bar 2 and the crochet main body 8 fixed thereto also move together with the outer cylinder 22 via the vertical shaft 26, the needle bar drive member 42, and the second annular ring 44. In this case, the slide piece drive rod 4 due to the operation of the first eccentric cam 36 disposed in the configuration position shown in FIG.
In addition, the distance that the slide piece S moves up and down is smaller than the distance that the needle bar 2 and the crochet main body 8 move up and down due to the operation of the second eccentric cam 50. The diagram shows the movement status of the slide piece S attached to the slide piece drive rod 4 and the crochet main body 8 attached to the needle bar 2 when the first eccentric cam 36 and the second eccentric cam 50 rotate 360 degrees, respectively. In FIG. 6, solid lines indicate the movement of the needle bar main body 8, and broken lines indicate the movement of the slide piece S.

FIG. 1 shows a state in which the first eccentric cam 36 and the second eccentric cam 50 are actuated by the rotation of the shafts 34 and 48 in the directions of the arrows, respectively, and the slide piece S and the crochet hook main body 8 are raised and lowered. FIG. 1A shows a state in which the hollowed out portion R of the crochet needle N is opened and passes through the fabric W and throat plate 168, and is about to rise while hooking the sewing thread 114 supplied from the rear looper 110. Now the first and second eccentric cams 3
6 and 50 are actuated by the rotation of their respective shafts 32 and 48, which rotate in the direction of the arrow.
The crochet main body 8 rises when the slide piece S is temporarily stopped, and both move in synchronization, so that the hollowed out part R of the crochet needle N accommodates the sewing thread midway, as shown in FIG. 1B. It is closed by a slide piece S. The entire crochet needle N, which remains closed, passes through the fabric W and rises to the position shown in FIG. 1C. However, at the initial stage when the slide piece S is about to descend from this position, the slide piece S stops moving, and only the crochet hook body 8 descends. After being released, the entire crochet needle N passes through the fabric W and descends, then receives sewing thread from the looper and hooks it into the hollowed out portion R. (Fig. 1 D, E). That is, the state returns to the state shown in FIG. 1A or FIG. 2. At this time, the fabric W is of course moved in a predetermined direction by the support frame 116 for the embroidery frame, and by repeating the above operation, a single chain stitch is formed on the fabric W.

In the crochet needle N according to the present invention, when the crochet needle N is inserted into the fabric W from above, its gouged part is in an open state, and the crochet needle is inserted through the fabric and the sewing thread is pulled up, and then the crochet needle N is inserted into the fabric W from above.
When the crochet needle moves upwards, the gouged part remains closed with the sewing thread accommodated inside the slide piece. This eliminates the problem of the threads of the fabric getting caught and rising, thereby preventing product defects. In addition, in order to adjust the moving position of the fabric W and the position of the hollowed out part R of the crochet needle N, in order to receive the sewing thread 114 from the looper 110 and form the desired stitch, it is necessary to adjust the directional position of the hollowed out part R of the crocheted needle N. Adjustments must be made. For this reason, it is necessary to rotate the crochet needle N and set the appropriate directional position of the recessed portion R thereof, and a needle bar and a slide piece drive rod rotation device b are employed. In other words, the bevel gear 64 caused by the rotation of the shaft 62 rotates the gear 58 attached to the outer cylinder 22 which meshes with the bevel gear 64, so that the needle bar 2 fixed to the outer cylinder 22 and the crochet hook N fixed thereto are rotated. Rotate in the same direction to adjust the direction of the gouged part R of the crochet hook N. Needless to say, the needle bar and slide piece drive rod rotating device b operates in continuous electrical and mechanical synchronization with the support frame 116 of the stabbing frame.

[Brief explanation of the drawing]

FIG. 1 shows the open/closed state of the gouged portion between the main body of the crochet needle and the slide piece according to the present invention, and from A to E in the same figure, the order of lowering → raising → lowering of the needle bar and the slide piece is illustrated. FIG. 2 is a longitudinal sectional view of various devices that participate in the upward and downward rotational movements of the crochet hook. Third
The figure is a schematic side view showing the positional relationship between a crochet hook and a looper. FIG. 4 is a top view of the annular ring that fits into the annular lifting ring of the slide piece drive rod, the first vertical shaft, and the slide piece drive member. Figure 5 is a cross-sectional view of the crochet hook. FIG. 6 is a curve diagram showing the movement relationship between the crochet main body and the slide piece as the pair of eccentric cams rotate. a...Needle bar and slide piece vertical drive device, b...Needle bar, slide piece drive rod rotation device, c...Nipple drive device, d...Presser drive device, N...Crochet hook, S...
Crochet slide piece, R...Curved hollow part, 2...Needle bar, 4...Slide piece drive rod, 8...Crochet main body, 1
0...Vertical groove, 12...Circular groove, 22...Outer cylinder,
25... Annular groove, 26... First vertical shaft, 28... Slide piece driving member, 30... First annular ring, 36... First eccentric cam, 34... Shaft, 38... Cam groove, 40... Projection or roller, 42 ...Needle bar driving member, 44...Second annular ring, 48...Shaft, 50...Second eccentric cam,
52...Cam groove, 54...Roller, 58...Bevel gear,
62...shaft, 64...umbrella gear.

Claims (1)

[Claims] 1. In a sewing machine having a crochet hook N in which a crochet slide piece S that can freely slide in a groove 10 provided on the side surface of a crochet main body 8 is movable to open or close a curved gouge portion R, the crochet slide piece S can be moved up and down within the needle bar 2. A circular groove 12 bored on the outer periphery of the end of the movable slide piece drive rod 4
A first annular ring 30 formed on one side of the slide piece driving member 28 which is slidably fitted onto a vertical shaft 26 separately provided in parallel with the needle bar 2 is fitted, and a first annular ring 30 formed on one side of the slide piece driving member 28 is fitted, and a protrusion formed on the other side is fitted. A slide piece vertical drive device formed by fitting a part or roller 40 into a cam groove 38 of a first eccentric cam 36 driven by rotation of a shaft 34, and an outer periphery of a needle bar 2 having a crochet main body 8 attached to an end thereof. The vertical shaft 2 is inserted into an annular groove 25 bored in an outer circumferential cylinder 22 fixed to
A second annular ring 44 provided on one side of the needle bar drive member 42 slidably fitted on the needle bar drive member 6 is fitted, and a protrusion or roller 54 protruding from the other side is driven by rotation of the shaft 48. A needle bar drive device that moves the needle bar 2 up and down, which is fitted into the cam groove 52 of the second eccentric cam 50, and a gear member 58, 6 that moves the needle bar outer peripheral cylinder 22.
4, and by rotating the crochet main body 8 together with the needle bar 2 and the slide piece S together with the slide piece drive rod 4 in a predetermined direction, the direction of the curved hollow part R of the crochet needle can be adjusted. When the crochet hook N is lowered and inserted into the fabric W from above, the curved gouge part R is provided.
is in the open state, the sewing thread 114 is captured by the curved hollowed-out portion R, and when the crochet needle N is raised and inserted into the fabric W from below again, the sewing thread 114 is caught by the curved hollowed-out portion R.
is a crochet opening/closing mechanism for a sewing machine, characterized in that it is closed by a crochet slide piece S while a sewing thread 114 is accommodated therein.