Lifting mechanism of rear tug device of multi-needle machine

Abstract

The utility model provides a lifting mechanism of a rear towing wheel device of a multi-needle machine, and belongs to the technical field of sewing machines. The lifting mechanism solves the problems that an existing lifting mechanism is complex in structure, large in occupied space and prone to collision. The multi-needle machine comprises a machine shell, a thread trimming motor and a rear dragging wheel device capable of moving up and down, the lifting mechanism comprises a wheel disc, a pull rod and a connecting rod assembly connected with the rear dragging wheel device, the thread trimming motor is a double-end motor, the wheel disc is fixed to a rotating shaft at one end of the thread trimming motor, and a sliding groove is formed in the wheel disc. The sliding groove comprises a driving section eccentrically arranged relative to the wheel disc and an arc-shaped avoiding section concentrically arranged with the wheel disc, a protruding sliding part is arranged at one end of the pull rod and embedded into the sliding groove, and the other end of the pull rod is connected with the connecting rod assembly. The special structures of the double-end motor and the wheel disc are matched, related structures such as a linear motor and a limiting mechanism are omitted, the overall structure is more compact, layout is more reasonable, occupied space is small, personnel collision caused by exposure of the motor is avoided, and safety is good.

Description

Technical Field

[0001] The utility model belongs to the technical field of sewing machines and relates to a lifting mechanism for a rear tug device of a multi-needle machine. Background Art

[0002] A multi-needle sewing machine is a sewing machine that can sew several lines of stitches at the same time. It has multiple needles, and the corresponding needles and threads are also fed simultaneously. There are many types of multi-needle machines, which are widely used in decorative sewing. According to the number of needles, multi-needle machines include 3-needle, 4-needle, 6-needle, 9-needle, 12-needle, 16-needle, 21-needle, 24-needle, 25-needle, 33-needle, 38-needle, and 50-needle sewing machines.

[0003] The existing multi-needle sewing machines all include a thread trimming mechanism and a thread feeding mechanism. The thread trimming mechanism includes a thread trimming motor arranged in the casing, and the thread trimming action is realized by driving the thread trimming motor. At the same time, in order to facilitate the feeding of fabrics during sewing, the existing multi-needle sewing machines are also provided with a rear drag mechanism, which includes a rear tug device and a linear motor. The linear motor is connected to one end of a crank swing rod, and the middle part of the crank swing rod is hinged on the casing. The other end of the crank swing rod is hinged to the rear tug device through a connecting rod assembly. The crank swing rod is driven by the linear motor to swing, thereby driving the rear tug device to be lifted and lowered, such as a rear drag mechanism of a multi-needle sewing machine disclosed in a Chinese patent application (application number: 202222947403.X).

[0004] In the above-mentioned multi-needle machine, due to the limitation of the space inside the casing, the linear motor is fixed on the outer wall of the casing, the crank rocker arm extends in the left and right directions and one end protrudes from the rear end of the casing, and a limiting mechanism for limiting the swing stroke of the crank rocker arm is also fixed at the rear end of the casing. The overall structure is complex, occupies a large space, and is prone to bumps, resulting in poor safety. Summary of the invention

[0005] The purpose of the utility model is to address the above-mentioned problems in the existing technology and propose a lifting mechanism for the rear tugwheel device of a multi-needle machine. The technical problem to be solved by the utility model is: how to solve the problem that the existing lifting mechanism has a complex structure, occupies a large space and is prone to bumps.

[0006] The purpose of the utility model can be achieved through the following technical solutions: a lifting mechanism for the rear tugwheel device of a multi-needle machine, the multi-needle machine comprising a casing, a thread trimming motor and a rear tugwheel device, the thread trimming motor is fixed in the casing, the rear tugwheel device can move up and down relative to the casing, the lifting mechanism comprises a connecting rod assembly connected to the rear tugwheel device, characterized in that the thread trimming motor is a double-headed motor, the lifting mechanism also comprises a wheel disc and a pull rod, the wheel disc is fixed on the rotating shaft at one end of the thread trimming motor, a slide groove is provided on the wheel disc, the slide groove comprises a driving section eccentrically arranged relative to the wheel disc and an arc-shaped avoidance section concentrically arranged with the wheel disc, one end of the pull rod has a protruding sliding portion and the sliding portion is embedded in the slide groove, and the other end of the pull rod is connected to the connecting rod assembly.

[0007] In the multi-needle machine, the thread trimming motor adopts a double-headed motor, one end of the thread trimming motor is connected to the thread trimming mechanism, and the other end of the thread trimming motor is fixed on the shaft, and a slide is set on the slide, and the driving section of the slide is eccentrically set. Taking the forward rotation of the motor to control the lifting of the rear tug device and the reverse rotation to control the thread trimming mechanism to trim the thread as an example, when the thread trimming motor rotates forward, the driving wheel rotates, and under the guidance of the inner wall of the eccentric driving section, the sliding part slides in the driving section to make the pull rod move to the left as a whole, thereby driving the connecting rod assembly to realize the lifting of the rear tug device, until the sliding part slides to abut against the closed end of the driving section to achieve the limit of its sliding stroke. The reverse rotation of the thread trimming motor causes the sliding part of the pull rod to separate from the driving section and enter the arc-shaped avoidance section, and the rear tug device descends and resets. When the thread trimming motor needs to switch to the thread trimming action, the thread trimming motor continues to reverse to drive the thread trimming mechanism to achieve thread trimming. At this time, the wheel disc reverses with the thread trimming motor, and the wheel disc slides relative to the sliding part of the pull rod along the arc direction of the arc avoidance section. The pull rod remains stationary and will not interfere with the reversal of the thread trimming motor. That is, during the thread trimming process, the wheel disc idles and the lifting mechanism does not move. This multi-needle machine integrates the drive of the thread trimming mechanism with the drive of the rear tug device lifting mechanism through the special structure of the double-head motor and the wheel disc, eliminating related structures such as linear motors and limit mechanisms. The structure is more compact and occupies less space. In addition, the motor will not be exposed, avoiding bumps caused by users, and has good safety.

[0008] In the lifting mechanism of the rear tug device of the multi-needle machine, one end of the driving section is connected to one end of the arc-shaped avoidance section, and the other end is bent along the radial direction of the wheel disc and arranged close to the center of the wheel disc. Through the above arrangement, the entire slide groove presents a hook-shaped structure, and the eccentrically arranged driving section is located at the hook portion. When rotating forward, it can drive the rear tug device to lift. When reversing, the inner wall of the driving section has a limiting buffering effect on the sliding part of the pull rod, thereby preventing the rear tug device from falling rapidly under the action of the reset spring.

[0009] In the lifting mechanism of the rear tug device of the multi-needle machine, a guide plate is fixed on the housing, and a guide groove is provided on the guide plate in the shape of a long strip and distributed along the left and right directions of the housing. A guide block is fixed at the end of the pull rod, and a protruding guide portion is provided on the guide block and the guide portion is slidably arranged in the guide groove, and the connecting rod assembly is connected to the guide block. Through the coordinated design of the guide plate and the guide block, the moving direction of the pull rod can be guided to avoid deflection, thereby ensuring the smooth lifting action of the rear tug device.

[0010] In the lifting mechanism of the rear tug device of the multi-needle machine, the connecting rod assembly includes an L-shaped crank, and connecting rods 1, 2 and 3, which are all in the shape of strip plates. One end of the connecting rod 1 is hinged to the guide block, one end of the connecting rod 2 has a strip hole, the other end of the connecting rod 1 passes through the strip hole through the hinge shaft and is hinged to the connecting rod 2, the other end of the connecting rod 2 is hinged to one end of the crank, the middle part of the crank is hinged to the housing, the other end of the crank is hinged to one end of the connecting rod 3, and the other end of the connecting rod 3 is hinged to the rear tug device. The end of the connecting rod 2 has a strip hole, so that it has a certain installation avoidance space, and the connection with the connecting rod 1 is more convenient. At the same time, the strip hole can provide a certain moving space for the hinge shaft, and can be replaced to ensure the smoothness of the swing between the connecting rods 1 and 2.

[0011] In the lifting mechanism of the rear tug device of the multi-needle machine, the thread trimming motor is arranged vertically, and the wheel is fixed on the rotating shaft at the upper end of the thread trimming motor. By arranging the thread trimming motor vertically, the space in the upper and lower directions of the casing can be more reasonably utilized, so that the lifting mechanism and the thread trimming mechanism are staggered in the upper and lower directions, which is convenient for layout and the whole structure is more compact.

[0012] In the lifting mechanism of the rear puller device of the multi-needle machine, the connecting rod 1 and the connecting rod 3 are both in the shape of a Z. Through the above arrangement, the layout of the space can be more reasonably utilized, making the structure more compact.

[0013] Compared with the prior art, the lifting mechanism of the rear tug device of the multi-needle machine has the following advantages: through the special structural coordination of the double-headed motor and the wheel disc, the linear motor and related structures such as the limit mechanism are eliminated, making the overall structure more compact, the layout more reasonable, the occupied space is greatly reduced, and the motor will not be exposed, avoiding bumps caused by users, and the safety is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a three-dimensional view of a multi-needle machine having a lifting mechanism of the rear tug device.

[0015] Figure 2 yes Figure 1 Enlarged view of point A in the middle.

[0016] Figure 3 It is a side view of a multi-needle machine having a lifting mechanism of the rear tug device.

[0017] Figure 4 It is a partial structural diagram of a multi-needle machine having a lifting mechanism of the rear tug device.

[0018] Figure 5 It is a three-dimensional image of a roulette wheel.

[0019] Figure 6 It is a three-dimensional diagram of the pull rod.

[0020] In the figure, 1, casing; 2, thread trimming motor; 3, rear tugwheel device; 3a, tugwheel frame; 3b, rear tugwheel; 3c, lifting rod; 3d; reset spring; 4, connecting rod assembly; 4a, connecting rod one; 4b, connecting rod two; 4b1, strip hole; 4c, crank; 4d, connecting rod three; 5, wheel plate; 5a, slide groove; 5a1, driving section; 5a2, arc avoidance section; 6, pull rod; 6a, sliding part; 6b, guide block; 6b1, guide part; 7, guide plate; 7a, guide groove. DETAILED DESCRIPTION

[0021] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0022] like Figure 1 , 3 As shown in FIG. 4 , the multi-needle machine includes a housing 1, a thread trimming motor 2, a rear tug device 3 and a thread trimming mechanism. The thread trimming motor 2 is a double-headed motor, which is fixed in the housing 1. The thread trimming mechanism is arranged at the lower part of the housing 1. The lower end of the rotating shaft of the thread trimming motor 2 is connected to the thread trimming mechanism and can drive the thread trimming mechanism to operate by reversing to realize the thread trimming action. The rear tug device 3 is arranged at the head of the right end of the housing 1 and can move up and down relative to the housing 1. The lifting mechanism includes a connecting rod assembly 4, a wheel 5 and a pull rod 6.

[0023] Specifically, if Figure 1 and 4 As shown, the rear tug device 3 includes a tug frame 3a, a rear tug 3b, a lifting rod 3c and a reset spring 3d, the lifting rod 3c is slidably connected to the housing 1, the tug frame 3a is fixedly connected to the lower end of the lifting rod 3c, the rear tug 3b is rotatably connected to the tug frame 3a, and the housing 1 is also provided with a driving mechanism capable of driving the rear tug 3b to rotate unidirectionally relative to the tug frame 3a. The middle part of the lifting rod 3c is also provided with a limit block, the reset spring 3d is sleeved on the lifting rod 3c and the two ends are respectively against the housing 1 and the limit block, and under the elastic force of the reset spring 3d, the rear tug device 3 is in a downward pressure state.

[0024] Further, if Figure 5 As shown, the wheel 5 is fixed on the rotating shaft at the upper end of the thread trimming motor 2, and a slide groove 5a is provided on the wheel 5. The slide groove 5a includes a driving section 5a1 eccentrically arranged relative to the wheel 5 and an arc-shaped avoidance section 5a2 concentrically arranged with the wheel 5. One end of the driving section 5a1 is connected to one end of the arc-shaped avoidance section 5a2, and the other end is bent along the radial direction of the wheel 5 and arranged close to the center of the wheel 5. The chord length direction of the arc-shaped avoidance section 5a2 is arranged at an acute angle to the extension direction of the driving section 5a1.

[0025] like Figure 2 and 6 As shown, a sliding block is fixed at one end of the pull rod 6, and the sliding block has a downwardly protruding sliding portion 6a, and the sliding portion 6a is embedded in the sliding groove 5a. A guide plate 7 is fixed on the housing 1, and a long strip of guide grooves 7a are provided on the guide plate 7 and are distributed along the left and right directions of the housing 1. A guide block 6b is fixed at the other end of the pull rod 6, and the guide block 6b has a protruding guide portion 6b1, and the guide portion 6b1 is slidably arranged in the guide groove 7a.

[0026] The connecting rod assembly 4 includes an L-shaped crank 4c, a long strip-shaped connecting rod 2 4b, and a Z-shaped connecting rod 1 4a and a connecting rod 3 4d. The connecting rod 1 4a is vertically arranged and the lower end of the connecting rod 1 4a is hinged to the guide block 6b, and an arc groove is also provided on the side of the end of the connecting rod 1 4a. The guide block 6b has a protruding sliding column, and the sliding column slides through the arc groove. The connecting rod 2 4b is horizontally arranged and has a strip hole 4b1 at one end. The upper end of the connecting rod 1 4a is hinged to the connecting rod 2 4b through the hinge shaft passing through the strip hole 4b1, and the other end of the connecting rod 2 4b is hinged to one end of the crank 4c, and the middle part of the crank 4c is hinged to the housing 1. The other end of the crank 4c is hinged to one end of the connecting rod 3 4d. The other end of the connecting rod 3 4d has a long hole in the shape of an elongated strip, and the connecting rod 3 4d passes through the long hole through a hinge axis and is hinged to the limit block on the lifting rod 3c.

[0027] The multi-needle machine controls the actions of the two mechanisms, the thread trimming mechanism and the rear tug device 3, through a single driving source of the thread trimming motor 2, and takes the forward rotation of the motor to control the lifting of the rear tug device 3 and the reverse rotation to control the thread trimming mechanism to trim the thread as an example. When the rear tug device 3 needs to be lifted, the thread trimming motor 2 is controlled to rotate forward to drive the wheel 5 to rotate forward, and the sliding portion 6a of the pull rod 6 slides along the slide groove 5a to the connection between the arc-shaped avoidance section 5a2 and the driving section 5a1, and the thread trimming motor 2 continues to rotate forward, and the sliding portion 6a slides into the eccentric driving section 5a1 and the pull rod 6 moves to the left under the action of the inner wall of the driving section 5a1, and then drives the connecting rod 1 4a, the connecting rod 2 4b, the crank 4c and the connecting rod 3 4d to work together, and drives the lifting rod 3c to overcome the elastic force of the reset spring 3d and lift upward, until the sliding portion 6a slides to abut against the closed end of the driving section 5a1 to achieve the limit of its sliding stroke. When the rear tug device 3 needs to be lowered, the thread trimming motor 2 is controlled to reverse, so that the sliding part 6a exits the driving section 5a1 and enters the arc-shaped avoidance section 5a2, and the lifting rod 3c moves downward under the elastic force of the reset spring 3d. When the thread trimming action is required, the thread trimming motor 2 is reversed, and the wheel 5 is reversed with the thread trimming motor 2. The wheel 5 slides relative to the pull rod 6 along the arc-shaped avoidance section 5a2, and the pull rod 6 does not move. That is, during the thread trimming process, the wheel 5 idles and the lifting mechanism does not move.

[0028] The multi-needle machine integrates the drive of the thread cutting mechanism with the drive of the lifting mechanism of the rear tugwheel device 3 through the special structure of the double-headed motor and the wheel 5, eliminating related structures such as the linear motor and the limit mechanism. The structure is more compact and occupies less space. The motor will not be exposed, which avoids bumps by users and has good safety.

[0029] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0030] Although this article uses more terms such as housing 1, wire trimming motor 2, rear tug device 3, tug frame 3a, rear tug 3b, lifting rod 3c; reset spring 3d, connecting rod assembly 4, connecting rod 1 4a, connecting rod 2 4b, bar hole 4b1, crank 4c, connecting rod 3 4d, wheel plate 5, slide 5a, driving section 5a1, arc avoidance section 5a2, pull rod 6, sliding part 6a, guide block 6b, guide part 6b1, guide plate 7, guide groove 7a, etc., it does not exclude the possibility of using other terms. The use of these terms is only to more conveniently describe and explain the essence of the utility model; interpreting them as any additional restrictions is contrary to the spirit of the utility model.

Claims

1. A lifting mechanism for a rear tug wheel device of a multi-needle machine, the multi-needle machine comprising a housing (1), a thread trimming motor (2) and a rear tug wheel device (3), the thread trimming motor (2) being fixed in the housing (1), the rear tug wheel device (3) being able to move up and down relative to the housing (1), the lifting mechanism comprising a connecting rod assembly (4) connected to the rear tug wheel device (3), characterized in that: The wire cutting motor (2) is a double-headed motor, and the lifting mechanism also includes a wheel disc (5) and a pull rod (6). The wheel disc (5) is fixed on a rotating shaft at one end of the wire cutting motor (2). A slide groove (5a) is provided on the wheel disc (5). The slide groove (5a) includes a driving section (5a1) eccentrically arranged relative to the wheel disc (5) and an arc-shaped avoidance section (5a2) concentrically arranged with the wheel disc (5). One end of the pull rod (6) has a protruding sliding portion (6a) and the sliding portion (6a) is embedded in the slide groove (5a). The other end of the pull rod (6) is connected to the connecting rod assembly (4).

2. The lifting mechanism of the rear puller device of the multi-needle machine according to claim 1, characterized in that: One end of the driving section (5a1) is connected to one end of the arc-shaped avoidance section (5a2), and the other end is bent along the radial direction of the wheel disc (5) and arranged close to the center of the wheel disc (5).

3. The lifting mechanism of the rear puller device of the multi-needle machine according to claim 1 or 2, characterized in that: A guide plate (7) is fixed on the casing (1), and a guide groove (7a) is provided on the guide plate (7) and is distributed along the left and right directions of the casing (1). A guide block (6b) is fixed at the end of the pull rod (6), and the guide block (6b) has a protruding guide portion (6b1) and the guide portion (6b1) is slidably arranged in the guide groove (7a). The connecting rod assembly (4) is connected to the guide block (6b).

4. The lifting mechanism of the rear puller device of the multi-needle machine according to claim 3, characterized in that: The connecting rod assembly (4) comprises an L-shaped crank (4c), and connecting rod one (4a), connecting rod two (4b) and connecting rod three (4d) all in the shape of strip plates, one end of the connecting rod one (4a) is hinged to the guide block (6b), one end of the connecting rod two (4b) has a strip hole (4b1), the other end of the connecting rod one (4a) passes through the strip hole (4b1) through a hinge shaft and is hinged to the connecting rod two (4b), the other end of the connecting rod two (4b) is hinged to one end of the crank (4c), the middle part of the crank (4c) is hinged to the casing (1), the other end of the crank (4c) is hinged to one end of the connecting rod three (4d), and the other end of the connecting rod three (4d) is hinged to the rear tug device (3).

5. The lifting mechanism of the rear puller device of the multi-needle machine according to claim 1 or 2, characterized in that: The thread trimming motor (2) is arranged vertically, and the wheel disc (5) is fixed on the rotating shaft at the upper end of the thread trimming motor (2).

6. The lifting mechanism of the rear puller device of the multi-needle machine according to claim 4, characterized in that: The connecting rod 1 (4a) and the connecting rod 3 (4d) are both Z-shaped.

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