Track cam thread hooking device and chain sewing machine

Abstract

The present invention discloses a track cam thread hooking device and a chain sewing machine, the track cam thread hooking device comprises a machine base, a track cam mechanism is movably provided on the machine base, a rocker and an eccentric member are respectively hinged on the follower of the track cam mechanism through two connecting rods, a connecting shaft is fixedly provided on the rocker away from the corresponding connecting rod end, the connecting shaft is slidably connected with the eccentric member, the eccentric member is eccentrically arranged on the machine base and its eccentric shaft is perpendicular to the connecting shaft, the connecting shaft movably passes through the machine base and a needle plate seat is fixedly sleeved at its end. The track cam thread hooking device of the present invention controls the hook needle seat to swing forward, backward, left and right through the track cam mechanism, simplifies the mechanical structure, is easy to maintain and adjust, and accelerates the swinging speed. The track cam thread hooking device is applied to the chain sewing machine, so that the hook needle and the machine needle move synchronously, and cooperate with the upper and lower presser feet and the feed dog to synchronously feed the material, and has the characteristics of high matching accuracy and simple structure.

Description

Technical Field

[0001] The invention belongs to the technical field of sewing machine equipment, and in particular relates to a track cam thread hooking device and a chain sewing machine. Background Art

[0002] Typically, interior components such as dashboards and door trims in cars or motor vehicles are sewn using sewing methods. The sewing stitches are generally flat seams, and column-type or cylinder-type flat seam sewing machines are typically used as sewing machines for forming the stitches.

[0003] Since the bottom thread of the lockstitch sewing machine is supplied by a bobbin, the amount of bottom thread wound on the bobbin is small when sewing a long sewn member such as an interior member, so the bobbin must be replaced frequently, which has a problem of significantly reducing productivity. In addition, the lockstitch stitch is not strictly formed in a straight line, and there is also a problem of slightly lacking a high-end feeling as a decoration, that is, in the process of forming the stitches by the lockstitch sewing machine, the stitches of each stitch are connected obliquely relative to the feeding direction of the sewn member, so the aesthetics are deteriorated.

[0004] Therefore, in recent years, as a decoration for interior components, the stitches formed by the chain stitch sewing machine have attracted attention. In the chain stitch sewing machine, the supply of the bottom thread does not require a bobbin, and the stitches of each stitch are parallel to the feeding direction of the sewn component, and the stitches are formed as a straight line as a whole, thus eliminating the above-mentioned problems caused by the lockstitch sewing machine.

[0005] Since various chain sewing machines on the market generally adopt eccentric cam, left and right thread hooks, swing needles, and thread stripping methods, each position cooperates synchronously and the mechanism is complex, maintenance and adjustment are relatively difficult, and there are problems such as unstable sewing stitches, loose lines and unclear stitches.

[0006] Therefore, the inventor is committed to designing a thread hooking device and a chain sewing machine to solve the above problems. Summary of the invention

[0007] The purpose of the present invention is to provide a track cam hooking device, which controls the hook needle seat to swing forward, backward, left and right through a track cam mechanism, simplifies the mechanical structure, facilitates maintenance and adjustment, and speeds up the swinging speed.

[0008] Another object of the present invention is to provide a chain sewing machine, in which a track cam hooking device with a simple mechanical structure is applied to the chain sewing machine, so that the hook and the needle can move synchronously, and the upper and lower presser feet and the feed dog can be used for synchronous comprehensive feeding, with high coordination accuracy and simple structure.

[0009] In order to achieve the above object, a technical solution adopted by the present invention is:

[0010] A track cam hooking device comprises a machine base, on which a track cam mechanism is movably provided, a rocker and an eccentric member are respectively hinged on the follower of the track cam mechanism through two connecting rods, a connecting shaft is fixedly provided on the rocker away from the corresponding connecting rod end, the connecting shaft is slidably connected to the eccentric member, the eccentric member is eccentrically arranged on the machine base and its eccentric shaft is perpendicular to the connecting shaft, the connecting shaft movably passes through the machine base and a needle plate seat is fixedly provided on its end.

[0011] Since the track cam mechanism has the advantages of simple structure, compactness, and convenient design, the present invention adopts the track cam mechanism to drive the rocker and the eccentric member to swing. Specifically, the follower of the track cam mechanism moves up and down, driving the two connecting rods to move, one of which pushes or pulls the rocker to swing around the axis of the connecting shaft, thereby driving the hook seat to swing back and forth, and the other connecting rod pushes or pulls the eccentric member to swing around its eccentric shaft. Since the eccentric member is slidingly connected to the connecting shaft, the connecting shaft swings left and right under the action of the eccentric member, thereby driving the hook seat to swing left and right.

[0012] The eccentric shaft of the eccentric piece of the present invention is vertically arranged to the connecting shaft, so that the eccentric piece can generate left and right and up and down forces on the connecting shaft under the action of the connecting rod. Combined with the sliding connection between the connecting shaft and the eccentric piece, the up and down forces on the connecting shaft are converted into sliding work between the connecting shaft and the eccentric piece, so that the connecting shaft swings left and right under the drive of the eccentric wheel.

[0013] As an improvement of the track cam hooking device of the present invention, the connecting shaft passes through the upper end of the eccentric and its two sides are respectively connected to the sliding grooves on the side of the eccentric wheel through upper sliders to slide up and down.

[0014] The connecting shaft and the eccentric wheel move up and down through the upper sliders on the left and right sides, so that the connecting shaft swings stably left and right under the action of the eccentric wheel.

[0015] As an improvement of the track cam hooking device of the present invention, a swing seat is provided outside the connecting shaft through a swing tight ring fixing sleeve, and the upper slider is fixedly connected to the swing seat through a fixed shaft.

[0016] As an improvement of the track cam hooking device of the present invention, the follower and the rocker are respectively hinged to the universal heads at the two ends of the corresponding connecting rod.

[0017] Since the universal head has the characteristic of flexible rolling, universal heads are arranged at both ends of the connecting rod connected to the rocker in the present invention, so that the swing of the rocker is more flexible, the swing angle and stability of the rocker can be adjusted automatically, and the push-pull force generated by the driven part is prevented from not matching the force required by the rocker.

[0018] As an improvement of the track cam hooking device of the present invention, the follower passes through the fixed panel of the machine base, and the follower is slidably connected to the fixed panel through a middle slider.

[0019] The middle slider has a certain limiting effect to prevent the position of the follower from being excessively offset during movement, thereby affecting the swing accuracy of the hook seat forward, backward, left and right.

[0020] As an improvement of the track cam hooking device of the present invention, the track cam of the track cam mechanism is slidably connected to the follower via a bearing, the bearing is located in the cam groove of the track cam and its inner ring is fixedly connected to the follower.

[0021] The cam groove forms a curved profile of the track cam, and the bearing slides in the cam groove. In order to prevent the follower from rotating, the inner ring of the bearing is connected to the follower and rotates relative to the outer ring, so that the follower swings up and down.

[0022] As an improvement of the track cam thread hooking device of the present invention, a lower sliding block is provided on the sliding sleeve of the rotating shaft of the track cam, and the lower sliding block is fixedly connected to the follower.

[0023] The driven member is slidably connected via the lower slider to prevent excessive friction from being generated during a slight swing of the driven member, thereby reducing the service life of the driven member and the rotating shaft.

[0024] Preferably, the follower comprises two push rods arranged side by side, one end of the two push rods is hinged to the two connecting rods respectively, the other end of the two push rods is slidingly connected to the two track cams respectively through the bearings, and the two track cams are coaxial.

[0025] In order to prevent the movement of the eccentric member and the rocker arm from influencing each other greatly, the present invention preferably has two push rods arranged side by side driven by different track cams to move up and down, thereby separately driving the eccentric member and the rocker arm to move, so that the forward and backward swinging and left and right swinging of the crochet hook seat have less mutual influence, thereby improving the swing accuracy of the crochet hook seat.

[0026] In order to achieve the above another object, a technical solution adopted by the present invention is:

[0027] A chain sewing machine comprises the above-mentioned track cam thread hooking device.

[0028] As an improvement of the chain sewing machine of the present invention, a needle plate seat is fixed on the fixed panel of the machine base, the hook needle seat is accommodated in the cavity of the needle plate seat, a feed rod that can swing back and forth is provided on one side of the needle plate seat, and the feed teeth on the top of the feed rod extend into the cavity and are flush with the needle plate surface of the needle plate seat.

[0029] The hook needle seat swings back and forth and left and right in the cavity of the needle plate seat to realize the functions of hooking the thread back and forth and swinging the hook needle left and right, and cooperates with the feed dog to swing back and forth in the cavity to feed the cloth, and the existing machine needle moves up and down. The sewing machine of the present invention is suitable for flat feeding, two-synchronization and three-synchronization comprehensive feeding, has the characteristics of fast sewing speed, and at the same time, the sewing seams are tighter and clearer.

[0030] Compared with the prior art, the track cam hooking device of the present invention adopts a track type cam mechanism, which controls the movement of the eccentric and the rocker arm respectively through two different connecting rods. The eccentric is slidably connected to the connecting shaft, so that the connecting shaft swings left and right, thereby driving the hook seat to swing left and right. At the same time, the rocker arm drives the hook to swing back and forth through the connecting shaft. The entire mechanical mechanism is simple and easy to maintain, adjust and control, thereby accelerating the swinging speed.

[0031] Compared with the prior art, the chain sewing machine of the present invention applies a track cam thread hooking device with a simple mechanical structure to the chain sewing machine, so that the movements of the hook and the needle are synchronized, and the upper and lower presser feet and the feed dogs are used for synchronous comprehensive feeding. It not only has high coordination accuracy and simple structure, but also can speed up the sewing speed, making the sewing seams tighter and clearer, and is suitable for flat feeding, two-synchronization and three-synchronization comprehensive feeding. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is an exploded view of the track cam thread hooking device and the needle plate cloth feeding assembly of the present invention;

[0033] Figure 2 It is a partial three-dimensional enlarged view of the track cam thread hooking device of the present invention;

[0034] Figure 3 It is a three-dimensional enlarged view of the crochet needle seat of the present invention;

[0035] Figure 4 It is a three-dimensional exploded enlarged view of the needle plate cloth feeding assembly of the present invention.

[0036] Illustration Description:

[0037] 1. Machine base, 11. Fixed panel, 111. Middle slider, 12. Fixed seat, 13. Cover plate, 2. Rotating shaft, 21. First track cam, 211. Cam groove, 212. First bearing, 22. Second track cam, 221. Second bearing, 23. Lower slider, 3. Follower, 31. Left and right swing push rod, 32. Forward and backward swing push rod, 4. First connecting rod, 5. Second connecting rod, 6. Eccentric member, 61. Eccentric shaft, 62. Upper slider, 7. Connecting shaft, 71. Rocker, 72. Swing seat, 73. Swing tight ring, 8. Hook needle seat, 81. Hook needle, 82. Locking screw, 83. Locking hole, 9. Needle plate feeding assembly, 91. Needle plate seat, 911. Needle plate surface, 92. Feed assembly, 921. Feed dog, 922. Feed rod. DETAILED DESCRIPTION

[0038] The following specifically describes the implementation modes of the present invention in conjunction with the accompanying drawings. The accompanying drawings are only for reference and illustration and do not constitute a limitation on the scope of patent protection of the present invention.

[0039] Reference Figures 1 to 3 A track cam hooking device includes a machine base 1, a track cam mechanism (not shown), two connecting rods (i.e., a first connecting rod 4 and a second connecting rod 5), a rocker 71, an eccentric member 6, a connecting shaft 7, a swing seat 72 and a hook seat 8. The present invention drives the hook seat 8 to swing back and forth and left and right through the track cam mechanism, thereby simplifying the mechanical structure.

[0040] Reference Figure 1 The base 1 includes a fixed panel 11, a fixed seat 12 and a cover plate 13. A middle slider 111 is slidably connected in a through hole on the fixed panel 11 through a pin. The fixed seat 12 is fixed on the fixed panel 11. The cover plate 13 is covered on the fixed seat 12 to form a cavity for installing other components.

[0041] Reference Figure 2The track cam mechanism is movably arranged on the machine base 1, and the track cam mechanism includes a follower 3, two track cams (i.e., the first track cam 21 and the second track cam 22) and two bearings (i.e., the first bearing 212 and the second bearing 221). The follower 3 includes two push rods arranged side by side, i.e., the front-back swing push rod 32 and the left-right swing push rod 31. The front-back swing push rod 32 and the left-right swing push rod 31 pass through the fixed panel 11 and the bottom of the fixed seat 12 from bottom to top in sequence. The middle slider 111 is fixed to the front-back swing The front and rear swing push rods 32 and the left and right swing push rods 31 are slidably connected to the fixed panel 11 to prevent the front and rear swing push rods 32 and the left and right swing push rods 31 from shaking to the side too much. At the same time, the friction resistance of the front and rear swing push rods 32 and the left and right swing push rods 31 is reduced. The front and rear swing push rods 32 and the left and right swing push rods 31 are located between the first track cam 21 and the second track cam 22. The first track cam 21 and the second track cam 22 are both located below the fixed panel 11 and The two are coaxial, that is, the second track cam 21 and the second track cam 22 are fixedly sleeved on the same rotating shaft 2, and the front and rear swing push rod 32 is slidably connected with the second track cam 22 through the second bearing 221. Specifically, a cam groove 211 is provided on the side of the first track cam 21, and the first bearing 212 is located in the cam groove 211 and its outer ring slides along the cam groove 211. The inner ring of the first bearing 212 is fixedly connected with the front and rear swing push rod 32 through a screw; the left and right swing push rod 31 is slidably connected with the second track cam 22 through the second bearing 221. Specifically, the shape of the second track cam 22 is symmetrical to that of the first track cam 21. Another cam groove (not shown) is provided on the side of the second track cam 22 close to the left and right swing push rod 31. The second bearing 221 is located in the cam groove and its outer ring slides along the cam groove. The inner ring of the second bearing 221 is fixedly connected with the left and right swing push rod 31 through a screw. A lower slider 23 is also slidably sleeved on the rotating shaft 2, and the lower slider 23 is fixed to the bottom of the left and right swing push rod 31 and the front and rear swing push rod 32.

[0042] Reference Figure 2 One end of the first connecting rod 4 is hinged to the upper end side of the front and rear swing push rod 32 through a universal head, and the other end of the first connecting rod 4 is hinged to the upper rocker 71 through another universal head. The connecting shaft 7 is fixed through the rocker 71 away from the end of the first connecting rod 4.

[0043] Reference Figure 2One end of the second connecting rod 5 is hinged to the eccentric member 6, and the other end of the second connecting rod 5 is hinged to the front of the upper end of the left and right swing push rods 31. The entire eccentric member 6 is L-shaped and eccentrically arranged on the fixed seat 12. The eccentric shaft 61 of the eccentric member 6 is fixed on the fixed seat 12. The four side surfaces of the upper end of the eccentric member 6 are U-shaped. The connecting shaft 7 passes through the fixed seat 12 in a gap and its outer fixed sleeve is provided with an annular swing tight ring 73. The swing seat 72 is fixedly sleeved outside the swing tight ring 73. The connecting shaft 7 and the swing tight ring 73 and the swing seat 72 pass through the upper end of the eccentric member 6, the eccentric shaft 61 of the eccentric member 6 is perpendicular to the connecting shaft 7, and the two opposite side surfaces of the eccentric member 6 are provided with sliding grooves (not marked), and an upper slider 62 is slidably accommodated in each sliding groove, and the fixed axis of the upper slider 62 is fixed to the front and rear side surfaces of the swing seat 72, so that the connecting shaft 7 and the swing seat 72 are connected to the eccentric member 6 by sliding up and down through the upper slider 62. In this embodiment, the two upper sliders 62 are symmetrically arranged and the axes of their fixed axes pass through the center of the connecting shaft 7.

[0044] Reference Figure 1 and Figure 3 One or more hooks 81 for hooking threads are provided at the upper end of the hook needle seat 8, and a locking hole 83 for locking the connecting shaft 7 is provided at the lower end of the hook needle seat 8. An opening is provided at the bottom of the locking hole 83, and the end of the connecting shaft 7 extends into the locking hole 83. The two locking screws 82 on the side of the hook needle seat 8 are locked so that the hook needle seat 8 is fixedly sleeved on the end of the connecting shaft 7, and the entire hook needle seat 8 is located outside the fixed seat 12.

[0045] Reference Figures 1 to 3 The working principle of the track cam hooking device of the present invention is as follows: the rotating shaft 2 rotates under the drive of external force, and the first track cam 21 and the second track cam 22 rotate accordingly. The first track cam 21 drives the front and rear swing push rod 32 to move up and down through the first bearing 212. The front and rear swing push rod 32 drives the rocker 71 to swing through the first connecting rod 4. The rocker 71 drives the hook seat 8 to swing back and forth through the connecting shaft 7. At the same time, the second track cam 22 drives the left and right swing push rod 31 to move up and down through the second bearing 221. The left and right swing push rod 31 drives the eccentric piece 6 to swing around its eccentric shaft 61 through the second connecting rod 5. The eccentric piece 6 slides up and down relative to the connecting shaft 7 through two upper sliders 62. The connecting shaft 7 swings left and right, thereby driving the hook seat 8 to swing left and right.

[0046] The track cam hooking device of the present invention adopts a track cam mechanism to control the separate actions of the eccentric and the rocker to realize the function of rapid swinging of the hook needle seat left and right and front and back, and has the characteristics of simple structure and easy maintenance, adjustment and control.

[0047] Reference Figures 1 to 4A chain sewing machine, the chain sewing machine includes the above-mentioned track cam hooking device and a needle plate feeding assembly 9, the needle plate feeding assembly 9 includes a needle plate seat 91 and a feeding assembly 92, the needle plate seat 91 is fixed on the fixed panel 11 and is located beside the fixed seat 12, the above-mentioned hook needle seat 8 is accommodated in the cavity of the needle plate seat 91, the top of the needle plate seat 91 is provided with a needle plate surface 911, and the needle plate surface 911 is provided with a clearance hole, and the feeding assembly 92 includes a base ( Not marked), a feed rod 922 that can swing back and forth and a feed tooth 921, the base is fixed on the fixed panel 11, the bottom end of the feed rod 922 is hinged to the base, the top end of the feed rod 922 is fixedly connected to the feed tooth 921, the feed rod 922 is located on the side of the needle plate seat 91, the feed tooth 921 extends into the cavity of the needle plate seat 91 and is flush with the needle plate surface 911, when the feed rod 922 swings back and forth driven by external force, the feed tooth 921 feeds cloth.

[0048] The fixed panel 11 of the chain sewing machine of the present invention is fixed on the desktop of the sewing machine (not shown in the figure), the fixed base 12, the cover plate 13 and the connecting shaft 7 are all located above the desktop of the sewing machine, and the rotating shaft 2 is driven to rotate by a motor or a pedal mechanism (not shown in the figure). Since one hook 81 needs to cooperate with one machine needle (not shown in the figure) to hook the thread, the sewing machine of the present invention can be provided with multiple hooks 81 on the hook base 8 and cooperate with multiple machine needles to form multiple sewing chain stitches.

[0049] The thread hooking principle of the sewing machine of the present invention is as follows: ① The presser foot (not shown) presses the sewing material onto the feed dog 921 at the needle plate surface 911; ② The needle with the upper thread passes through the sewing material and moves down to the lower dead point in the cavity of the needle plate seat 91, and then rises a certain distance from the lower dead point, and the upper thread forms a thread loop on one side of the needle; ③ The above-mentioned track cam thread hooking device drives the hook needle 81 with the bottom thread to swing left and right and back and forth to align with the thread loop and hook into the thread loop; ④ The needle rises and punctures the sewing material for the second time, and when it rises to At the upper end of the sewing material, the feed dog 921 pushes the sewing material a stitch distance, the needle falls and pierces the sewing material, and the feed dog 921 stops feeding; ⑤ The hook 81 retreats, and the needle penetrates the thread loop of the hook 81 (i.e. the bottom line triangle circle) when it pierces the sewing material and meets the hook 81; ⑥ When the needle falls to the bottom dead point, the thread loop of the previous stitch hole is pulled to the bottom surface of the sewing material, and the bottom line of the hook 81 slides up to the bottom plane of the needle plate close to the needle; ⑦ The above reciprocating cycle forms a chain sewing stitch.

[0050] The chain sewing machine of the present invention applies a track cam thread hooking device with a simple mechanical structure to the chain sewing machine. The left and right, front and back swinging movements of the hook needle need to be synchronized with the up and down movement of the sewing machine needle. At the same time, the upper and lower presser feet and feed dogs of the sewing machine are used for synchronous comprehensive feeding. Not only is the coordination accuracy high and the structure simple, but it can also speed up the sewing speed, making the sewing seams tighter and clearer. It is suitable for flat feeding, two-synchronization and three-synchronization comprehensive feeding.

[0051] The above disclosure is only a preferred embodiment of the present invention, which cannot be used to limit the scope of protection of the present invention. Therefore, equivalent changes made within the scope of the patent application of the present invention are still within the scope covered by the present invention.

Claims

1. A track cam hooking device, comprising a base, characterized in that: A track cam mechanism is movably provided on the machine base, and a follower of the track cam mechanism is respectively hinged with a rocker and an eccentric member through two connecting rods, and a connecting shaft is fixedly provided on the rocker away from the corresponding connecting rod end, and the connecting shaft is slidably connected with the eccentric member, and the eccentric member is eccentrically arranged on the machine base and its eccentric shaft is perpendicular to the connecting shaft, and the connecting shaft movably passes through the machine base and a needle plate seat is fixedly provided at its end; The track cam of the track cam mechanism is slidably connected to the follower via a bearing, the bearing is located in the cam groove of the track cam and its inner ring is fixedly connected to the follower; The driven member comprises two push rods arranged side by side, one end of the two push rods is respectively hinged to one of the two connecting rods, the other ends of the two push rods are respectively slidably connected to the two track cams through the bearings, and the two track cams are coaxial; It also includes a hook needle seat, and a locking hole for locking the connecting shaft is provided at the lower end of the hook needle seat.

2. The track cam thread hooking device according to claim 1, characterized in that: The connecting shaft passes through the upper end of the eccentric member, and two sides thereof are respectively connected to the sliding grooves on the side surfaces of the eccentric member by sliding up and down through upper sliding blocks.

3. The track cam thread hooking device according to claim 2, characterized in that: A swing seat is fixedly sleeved outside the connecting shaft via a swing tight ring, and the upper sliding block is fixedly connected to the swing seat via a fixed shaft.

4. The track cam thread hooking device according to claim 1, characterized in that: The driven member and the rocker are respectively hinged to the universal heads at the two ends of the corresponding connecting rod.

5. The track cam thread hooking device according to claim 1, characterized in that: The driven member passes through the fixed panel of the base, and the driven member is slidably connected with the fixed panel via a middle slider.

6. The track cam thread hooking device according to claim 1, characterized in that: A lower sliding block is provided on the sliding sleeve of the rotating shaft of the track cam, and the lower sliding block is fixedly connected to the driven member.

7. A chain stitch sewing machine, characterized in that: It comprises the track cam line hooking device as claimed in claim 1.

8. The chain stitch sewing machine according to claim 7, characterized in that: A needle plate seat is fixed on the fixed panel of the machine base, and the hook needle seat is accommodated in the cavity of the needle plate seat. A feed rod that can swing back and forth is provided on one side of the needle plate seat, and the feed teeth on the top of the feed rod extend into the cavity and are flush with the needle plate surface of the needle plate seat.

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