CN115110213A

CN115110213A - Looper thread hooking mechanism and sewing machine

Info

Publication number: CN115110213A
Application number: CN202110287586.4A
Authority: CN
Inventors: 沈剑青; 邱志伟; 洪志敏; 林晓晓
Original assignee: Jack Technology Co Ltd
Current assignee: Jack Technology Co Ltd
Priority date: 2021-03-17
Filing date: 2021-03-17
Publication date: 2022-09-27
Anticipated expiration: 2041-03-17
Also published as: CN115110213B

Abstract

The invention provides a looper thread hooking mechanism which comprises a rotary driving device, a looper support, a looper and a lead screw, wherein the rotary driving device drives a rotating shaft to rotate; the lead screw includes screw rod and movable block, the screw rod is on a parallel with the length direction of pivot, the movable block is followed linear motion is to the screw rod, and with the looper support is connected, drives the looper support is followed the length direction of pivot removes. The invention also provides a sewing machine which comprises the looper thread hooking mechanism. The invention has the advantages that the rotary driving device and the lead screw are adopted to drive the looper thread hooking mechanism to perform composite motion, the types of parts are reduced, the existing assembly time is reduced, the assembly is convenient, and the noise generated by the looper gear is reduced.

Description

Looper thread hooking mechanism and sewing machine

Technical Field

The invention relates to a looper thread hooking mechanism and a sewing machine with the same.

Background

The existing chain stitch needs to be additionally provided with a plurality of parts to realize the motion of a curved needle, such as a curved needle gear, a curved needle shaft, a needle protecting shaft, a cross pendulum shaft, a housing, a curved needle frame seat and the like, and a needle protecting mechanism is arranged near the curved needle and can be contacted with the needle when the curved needle catches a thread loop to prevent the needle from swinging. The too large number of parts of the looper thread hooking mechanism and the needle protection mechanism brings inconvenience to assembly, the precision requirement of the looper gear is high, and the noise of the whole machine is increased.

Disclosure of Invention

In view of the above-mentioned drawbacks, the present invention provides a looper thread hooking mechanism with simple structure and easy assembly and adjustment.

The invention provides a looper thread hooking mechanism which comprises a rotary driving device, a looper support, a looper and a lead screw, wherein the rotary driving device drives a rotating shaft to rotate; the lead screw includes screw rod and movable block, the screw rod is on a parallel with the length direction of pivot, the movable block is followed linear motion is to the screw rod, and with the looper support is connected, drives the looper support is followed the length direction of pivot removes.

Preferably, the screw is driven to rotate by another rotary drive.

Preferably, one end of the screw rod is fixed, the other end of the screw rod is coaxially connected with the rotating shaft, and an arc-shaped groove is formed in the curved needle support; the looper colludes line mechanism and still includes the connecting rod, the one end setting of connecting rod is in on the movable block, the other end with arc wall swing joint to be equipped with first locating part and second locating part, the arc wall is located between first locating part and the second locating part, and leave the clearance respectively between the two.

Preferably, the looper thread hooking mechanism further comprises a fixed protection needle fixedly installed.

Preferably, the looper colludes line mechanism and still includes slide rail, swing and protects needle support and swing and protect the needle, slide rail fixed mounting, the swing protects the needle setting and is in on the needle support is protected in the swing, swing protect needle support, movable block respectively with slide rail sliding connection, the swing protects the needle support and is located between the front side of movable block and the rear side of slide rail to respectively with both telescopic connection.

Preferably, a spring or an air cylinder is respectively arranged between the swing needle protection support and the movable block and between the swing needle protection support and the sliding rail.

Preferably, the looper thread hooking mechanism further comprises a support base fixedly mounted, and one ends of the rotary driving device, the sliding rail and the screw rod are all arranged on the support base.

Preferably, an adjusting screw, an adjusting spring and a steel ball are further sequentially arranged in the curved needle support from outside to inside, and the adjusting screw, the adjusting spring and the steel ball are used for adjusting the friction force between the curved needle support and the rotating shaft.

Preferably, a key groove is formed in the rotating shaft, a key block is arranged in the key groove, and the curved needle support is in sliding fit with the key block.

The invention also provides a sewing machine which comprises the looper thread hooking mechanism.

The invention has the advantages that the rotary driving device and the lead screw are adopted to drive the compound motion of the looper thread hooking mechanism, the complex connecting structure mainly comprising a looper gear is eliminated, the variety of parts is reduced, the existing assembly time is reduced, the assembly is convenient, the noise generated by the looper gear is reduced, and the hidden danger of oil leakage of the looper housing is reduced; the whole movement is modularized, the difference caused by manual work on the curved needle is reduced, and the effect of protecting the machine needle by swinging the needle guard is realized.

Drawings

FIG. 1 is an exploded view of the looper thread take-up mechanism of the present invention;

FIG. 2 is a first perspective view of the looper thread take-up mechanism of the present invention;

FIG. 3 is a second perspective view of the looper thread take-up mechanism of the present invention;

FIG. 4 is a rotational phase diagram of the rotational drive apparatus;

fig. 5 is a schematic diagram of the motion track of the curved needle.

Element number description:

1 Rotary drive device

2 fixed needle protection bracket

3 set screw

4 fixed protective needle

5 set screw

6 rotating shaft

61 key groove

7 key block

81 first limiting part

82 second limiting part

9 curved needle support

91 arc-shaped groove

10 steel ball

11 adjusting spring

12 adjusting screw

13 shaft coupling

14 set screw

15 curved needle

16 screw

17 connecting rod

18 slide rail

19 first guide pin

20 movable block

21 check ring

22 bearing

23 bearing sleeve

24 pushing frame

25 set screw

26 oscillating guard needle

271 first spring

272 second spring

28 swing needle protection support

29 second guide pin

30 support base

Detailed Description

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings. These embodiments are merely illustrative of the present invention and are not intended to limit the present invention.

In the description of the present invention, it should be noted that the terms "front", "back", "left", "right", "inner", "outer", "top", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Fig. 1 is an exploded view of the looper thread hooking mechanism of the present invention, and in the following description, with reference to the drawing in fig. 1 as a direction, the side where the rotary driving device 1 is located is a rear side, the side where the bearing housing 23 is located is a front side, the side where the holder base 30 is located is a right side, and the side opposite to the holder base 30 is a left side.

Example one

As shown in fig. 1-3, the first embodiment provides a looper thread hooking mechanism, which comprises a rotary driving device 1, a looper bracket 9, a looper 15, a lead screw and a connecting rod 17. Wherein, the rotary driving device 1 is fixedly arranged and drives the rotating shaft 6 to rotate. The rotation driving device 1 may be a stepping motor or a bidirectional rotation cylinder, and the rotating shaft 6 is preferably a motor shaft or a cylinder output shaft, and may also be a shaft body coaxially connected with the motor shaft or the cylinder output shaft. A key groove 61 is formed in the rotating shaft 6, a key block 7 is arranged in the key groove 61, and an opening is formed in the bottom of the curved needle support 9 and is in sliding fit with the key block 7 and the rotating shaft 6. The curved needle 15 is fixed at the top of the curved needle support 9 through the set screw 5, so that the curved needle 15 can synchronously rotate along with the rotating shaft 6 to move left and right and can be driven to move back and forth along the length direction of the rotating shaft 6 to realize compound motion on a horizontal plane, further finish the actions of hooking and rubbing the back and avoid the machine needle. The looper support 9 is also internally and sequentially provided with an adjusting screw 12, an adjusting spring 11 and a steel ball 10 from outside to inside, the adjusting screw 12 is screwed or loosened to control the pressure of the adjusting spring 11 on the steel ball 10, so that the friction force between the looper support 9 and the rotating shaft 6 is changed, and meanwhile, the position stability of the looper support 9 is ensured, and the looper support cannot run off due to large gap.

In order to realize the back and forth movement of the curved needle 15, the screw rod comprises a screw rod 16 and a movable block 20, and the movable block 20 moves linearly along the screw rod 16. The screw 16 is parallel to the longitudinal direction of the rotating shaft 6, and has one end fixed and the other end coaxially connected to the rotating shaft 6 via a coupling 13 and a set screw 14. By adjusting the tightness of the set screw 14, the screw 16 and the shaft 6 can be assisted to adapt to changes caused by parameter adjustment of the rotary drive 1. The curved needle support 9 is provided with an arc-shaped groove 91, one end of the connecting rod 17 is fixed on the movable block 20, the other end of the connecting rod is movably connected with the arc-shaped groove 91, the connecting rod is provided with a first limiting part 81 positioned at the front side of the arc-shaped groove 91 and a second limiting part 82 positioned at the rear side of the arc-shaped groove 91, the arc-shaped groove 91 is positioned between the first limiting part 81 and the second limiting part 82, and a gap is respectively reserved between the first limiting part 81 and the second limiting part 82 and between the first limiting part 81 and the second limiting part.

In order to support and protect the needle, the needle bending and hooking mechanism further comprises a slide rail 18, a swing needle protection support 28 and a swing needle protection 26, the slide rail 18 is fixedly installed, the swing needle protection 26 is arranged at the top of the swing needle protection support 28, the swing needle protection support 28 and the movable block 20 are respectively in sliding connection with the slide rail 18, and the swing needle protection support 28 is arranged between the front side of the movable block 20 and the rear side of the slide rail 18 and respectively in telescopic connection with the front side and the rear side of the movable block 20. Specifically, an L-shaped pushing frame 24 is mounted on the movable block 20 through a fixing screw 25, a first guide pin 19 is disposed on each of a front side surface of the pushing frame 24 and a rear side surface of the slide rail 18, a second guide pin 29 is disposed in the swing needle protection bracket 28 in a penetrating manner, a first spring 271 is disposed between the first guide pin 19 and the second guide pin 29 of the pushing frame 24, and a second spring 272 is disposed between the first guide pin 19 and the second guide pin 29 of the slide rail 18. The skilled person can also replace the spring and guide pin with a cylinder as required, which can also serve as a telescopic connection. The looper thread hooking mechanism further comprises a fixed protective needle 4 fixedly installed, the fixed protective needle 4 is fixedly connected with the rotary driving device 1 through a fixed protective needle support 2 and a fixing screw 3, and the fixed protective needle 4 is located on the rear side of the swing protective needle 26.

In order to facilitate assembly and fixation, the looper thread hooking mechanism further comprises a support base 30 fixedly installed in a sewing machine shell, the rotary driving device 1, the slide rail 18 and one end of the screw 16 are all arranged on the support base 30, wherein one end of the screw 16 is rotatably supported on the support base 30 through a retainer ring 21, a bearing 22 and a bearing sleeve 23 in sequence from back to front.

When the rotary driving device 1 drives the rotating shaft 6 to rotate, the rotating shaft 6 can drive the screw rod 16 to rotate due to the existence of the coupler 13, the screw rod 16 drives the movable block 20 to reciprocate, and the first limiting piece 81 and the second limiting piece 82 are not tightly screwed to the curved needle support 9 and have gaps, so that the curved needle support 9 can only rotate along with the rotating shaft 6 within a certain time, and the curved needle 15 can horizontally move left and right in the process; when the first limiting member 81 or the second limiting member 82 clings to the looper bracket 9, the looper bracket 9 moves back and forth along the rotating shaft 6 under the pushing of the first limiting member 81 or the second limiting member 82, so that the looper 15 moves in the left-right direction and the front-back direction at the same time in the process to form a section of non-linear track.

The working process of the looper thread hooking mechanism of the invention is described with reference to fig. 1 to 3 in conjunction with fig. 4 and 5:

a first gap is defined as a gap between the first limiting member 81 and the looper support 9 (i.e., the arc-shaped slot 91), and a second gap is defined as a gap between the second limiting member 82 and the looper support 9.

S1, the rotating shaft 6 of the rotation driving device 1 rotates counterclockwise from the point C' at the right end, the screw 16 drives the movable block 20 to move backward, the needle starts to rise from the lowest point, the second gap is 0, the first gap is at the maximum, and the first spring 271 is in a natural state. When the rotating shaft 6 rotates to the point F along the direction C' F, the needle is positioned at the point to be protected, the swinging needle guard 26 is blocked by the fixed needle guard 4 to reach the limiting point and does not move backwards any more, and the swinging needle guard starts to be in contact with the front part of the needle to protect the needle, the second gap is gradually increased in the process, the first gap is gradually reduced, and the second spring 272 is in a compressed state. Then, the rotating shaft 6 rotates along FB to point B, where the first gap is 0, the second gap is at the maximum, the needle is in the ascending phase, the movable block 20 continues to move backward, and the first spring 271 is always in the compressed state due to the compression. In the process that the rotating shaft 6 rotates from the point C 'to the point B, the looper support 9 only rotates along with the rotating shaft 6, the motion track formed by the looper 15 is E' D, namely the looper 15 swings from right to left, and the looper 15 hooks a thread in the process.

S2, when the rotating shaft 6 rotates to point C along BC, the first spring 271 is compressed to the bottom, and the needle reaches the highest point at C. Since the first gap is 0 and the movable block 20 moves backward continuously in the process, the connecting rod 17 and the first limiting member 81 push the looper support 9 to move backward along the rotating shaft 6, and meanwhile, the looper support 9 still rotates counterclockwise along with the rotating shaft 6, the motion track formed by the looper 15 is DE, and the motion track moves from the front of the needle to the back of the needle, so that a space is reserved for the subsequent descending of the needle.

S3, the rotating shaft 6 rotates clockwise from the point C at the left end, the screw 16 drives the movable block 20 to move forward, the needle starts to descend at the highest point, the second gap is at the maximum value at the moment, and the first gap is 0. When the rotating shaft 6 rotates to the point B 'along CB', the first gap is enlarged and the second gap is reduced in the process until the second gap is 0, the first spring 271 and the second spring 272 start to reset, and the needle descends. During the process of rotating the rotating shaft 6 from the point C to the point B ', the looper support 9 only rotates along with the rotating shaft 6, and the motion track formed by the looper 15 is ED', that is, the looper swings from left to right.

S4, the rotating shaft 6 rotates to the point C 'along the point B' C ', the first spring 271 and the second spring 272 are completely reset at the point C', and the natural state is restored. Since the second gap is 0 in the process, the movable block 20 continuously moves forward, the connecting rod 17 and the second limiting member 82 push the looper support 9 to move forward along the rotating shaft 6, and meanwhile, the looper support 9 still moves clockwise along with the rotating shaft 6, so that the motion track formed by the looper 15 is D 'E'. As the needle descends, the looper 15 will pass through the side of the needle (i.e., the looper rubs against the back) in preparation for subsequent threading. The second spring 272 pushes the swing guard 26 to move forward during the forward movement of the movable block 20 and the return process of the first spring 271, so as to leave a space for the needle to descend. When the needle is at the lowest point, the adjustment can be carried out in the following way:

1. adjusting the starting angle of the rotary driving device 1, and further adjusting the opening distance between the curved needle and the needle;

2. the rotation angle of the rotary driving device 1 is adjusted, so that the length of the left-right movement of the curved needle is adjusted, and the proportion of the time period for realizing the opening distance in the whole movement track period is changed;

3. the gap distance between the first limiting part 81 and the second limiting part 82 and the looper bracket 9 is adjusted, so as to adjust the back rubbing time of the looper.

The shape of the non-linear section in the motion trajectory of the curved needle shown in fig. 5 varies with the parameters of the screw 16 and the corresponding changes in the rotation of the rotary drive 1, and is not limited to the arc shown in the figure. In addition, the time ratios of the straight line segment and the non-straight line segment in fig. 4 and 5 are only schematic and do not represent the real time ratios.

Example two

The second embodiment differs from the first embodiment in that the connecting rod 17, the first stopper 81 and the second stopper 82 are eliminated, and three rotary driving devices and two lead screws are used to drive the looper and the swing guard, respectively. Wherein the bent needle bracket is sleeved on a rotating shaft of the first rotary driving device and rotates synchronously with the rotating shaft; the second rotary driving device drives a screw rod to rotate, and a movable block of the screw rod is connected with the curved needle support and used for driving the curved needle support to move back and forth; the third rotary driving device drives the other lead screw, and the movable block of the lead screw adopts the same connecting structure as the first embodiment, namely comprises a pushing frame, a swinging needle protection bracket, a swinging needle protection and a sliding rail, so that the forward and backward movement of the swinging needle protection is controlled.

The technical personnel in the field can also adjust the number of the rotary driving device and the screw rod according to the requirements, and can meet the requirements of controlling the front and back movement and the left and right movement of the curved needle and the requirements of swinging the protective needle to move back and forth.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, many modifications and substitutions can be made without departing from the technical principle of the present invention, and these modifications and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. A looper thread hooking mechanism is characterized by comprising a rotary driving device (1), a looper bracket (9), a looper (15) and a screw rod,

the rotary driving device (1) drives the rotating shaft (6) to rotate, the curved needle (15) is arranged on the curved needle support (9), and the curved needle support (9) is movably connected with the rotating shaft (6) and can synchronously rotate with the rotating shaft (6) and move along the length direction of the rotating shaft (6);

the lead screw includes screw rod (16) and movable block (20), screw rod (16) are on a parallel with the length direction of pivot (6), movable block (20) are followed screw rod (16) are linear motion, and with looper support (9) are connected, drive looper support (9) are followed the length direction of pivot (6) removes.

2. Looper thread take-up mechanism according to claim 1, characterized in that the threaded rod (16) is driven in rotation by a further rotary drive.

3. The looper thread take-off mechanism of claim 1, wherein one end of the screw (16) is fixed, the other end is coaxially connected with the rotating shaft (6), and an arc-shaped groove (91) is formed on the looper bracket (9);

looper colludes line mechanism still includes connecting rod (17), the one end setting of connecting rod (17) is in on movable block (20), the other end with arc wall (91) swing joint to be equipped with first locating part (81) and second locating part (82), arc wall (91) are located between first locating part (81) and second locating part (82), and leave the clearance between the two respectively.

4. Looper thread take-up mechanism according to claim 1 or 3, characterized in that it further comprises a stationary guard (4) fixedly mounted.

5. The looper thread take-up mechanism according to claim 3, further comprising a slide rail (18), a swinging needle protection bracket (28) and a swinging needle protection (26), wherein the slide rail (18) is fixedly mounted, the swinging needle protection (26) is disposed on the swinging needle protection bracket (28), the swinging needle protection bracket (28) and the movable block (20) are respectively slidably connected with the slide rail (18), and the swinging needle protection bracket (28) is located between the front side of the movable block (20) and the rear side of the slide rail (18) and respectively telescopically connected with the front side and the rear side of the movable block (20).

6. Looper thread take-up mechanism according to claim 5, characterized in that a spring or a cylinder is provided between the swing needle guard support (28) and the movable block (20) and the slide rail (18), respectively.

7. The looper thread take-off mechanism according to claim 5, further comprising a fixedly mounted support base (30), wherein one end of the rotary drive device (1), the slide rail (18) and the screw (16) are disposed on the support base (30).

8. The looper thread take-up mechanism according to claim 1, wherein an adjusting screw (12), an adjusting spring (11) and a steel ball (10) are further provided in the looper support (9) from outside to inside in sequence for adjusting the friction force between the looper support (9) and the rotary shaft (6).

9. The looper thread take-off mechanism according to claim 1, wherein a key groove (61) is formed in the rotating shaft (6), a key block (7) is arranged in the key groove (61), and the looper support (9) is in sliding fit with the key block (7).

10. A sewing machine comprising the looper thread take-up mechanism of claim 1.