阅读说明：本技术 一种服装车缝的辅助张紧送料装置及缝纫机 (Supplementary tensioning material feeding unit and sewing machine of clothing sewing ) 是由 胡启明 于 2021-07-20 设计创作，主要内容包括：本发明公开了一种服装车缝的辅助张紧送料装置及缝纫机,其中,辅助张紧送料装置包括张紧架以及滚轮组件,滚轮组件设置在所述张紧架上；所述滚轮组件包括滚动轮组件以及张紧轮组件,沿着衣服前进的方向,所述滚动轮组件包括前滚动轮、后滚动轮以及用于驱动前滚动轮跟随后滚动轮转动的传动机构,所述张紧轮组件包括位于工作台下方的张紧轮以及用于调节所述张紧轮沿前后方向移动的调节机构。本发明的辅助张紧送料装置在缝制带有松紧带的裤头时,既能够保证工作台前后部分布料的平整性,而且还能保证布料的前进轨迹更平直。(The invention discloses an auxiliary tensioning feeding device for clothing sewing and a sewing machine, wherein the auxiliary tensioning feeding device comprises a tensioning frame and a roller assembly, and the roller assembly is arranged on the tensioning frame; the roller assembly comprises a rolling wheel assembly and a tensioning wheel assembly, the rolling wheel assembly comprises a front rolling wheel, a rear rolling wheel and a transmission mechanism used for driving the front rolling wheel to rotate along with the rear rolling wheel, and the tensioning wheel assembly comprises a tensioning wheel located below the workbench and an adjusting mechanism used for adjusting the tensioning wheel to move in the front-back direction. When the auxiliary tensioning feeding device is used for sewing the underpants with the elastic bands, the smoothness of cloth distributed on the front and rear parts of the workbench can be ensured, and the forward track of the cloth can be ensured to be straighter.)

1. An auxiliary tensioning feeding device for clothing sewing comprises a tensioning frame and a roller assembly for tensioning underpants, wherein the roller assembly is arranged on the tensioning frame; the roller assembly comprises a rolling wheel assembly and a tensioning wheel assembly, the rolling wheel assembly is arranged in the advancing direction of clothes and comprises a front rolling wheel located in the front of the workbench, a rear rolling wheel located at the rear of the workbench and a transmission mechanism used for driving the front rolling wheel to follow the rear rolling wheel to rotate, and the tensioning wheel assembly comprises a tensioning wheel located below the workbench and an adjusting mechanism used for adjusting the tensioning wheel to move in the front-rear direction.

2. The auxiliary tensioning feeding device for the garment sewing machine according to claim 1, wherein the length direction of the tensioning frame is perpendicular to the length direction of the workbench, the tensioning frame comprises a bottom plate and a side plate arranged on the bottom plate, the side plate stretches across the workbench, and a position of the side plate, where the workbench is located, is provided with a space avoiding position; the front rolling wheel, the rear rolling wheel and the tension wheel are all arranged on the side plates.

3. The auxiliary tensioning feeding device for the garment sewing machine as claimed in claim 2, wherein the front rolling wheel comprises a front rolling wheel body and a front rolling shaft coaxially arranged with the front rolling wheel body, one end of the front rolling shaft is connected with one end of the front rolling wheel body, and the other end of the front rolling shaft extends outwards; the rear rolling wheel comprises a rear roller body and a rear rolling shaft which is coaxially arranged with the rear roller body, one end of the rear rolling shaft is connected with one end of the rear roller body, and the other end of the rear rolling shaft extends outwards; the front rolling shaft is arranged in front of the side plate through a bearing, and the rear rolling shaft is arranged behind the side plate through a bearing; the axes of the front rolling shaft and the rear rolling shaft are both vertical to the advancing direction of the clothes.

4. The auxiliary tensioning feeding device for the garment sewing machine as claimed in claim 3, wherein the transmission mechanism comprises a first synchronizing wheel arranged on the rear rolling shaft, a second synchronizing wheel arranged on the side plate through a bearing, a third synchronizing wheel arranged on the side plate through a bearing, a fourth synchronizing wheel arranged on the front rolling shaft, a first synchronizing belt, a second synchronizing belt and a third synchronizing belt, wherein the second synchronizing wheel is located below the first synchronizing wheel, the third synchronizing wheel is located below the fourth synchronizing wheel, the first synchronizing belt is arranged between the first synchronizing wheel and the second synchronizing wheel, the second synchronizing belt is arranged between the second synchronizing wheel and the third synchronizing wheel, and the third synchronizing belt is arranged between the third synchronizing wheel and the fourth synchronizing wheel.

5. The auxiliary tensioning feeding device for the garment sewing machine as claimed in claim 4, wherein the linear speed of the front rolling wheel is greater than that of the rear rolling wheel.

6. The auxiliary tensioning feeding device for the garment sewing machine according to claim 4, wherein the first synchronizing wheel, the second synchronizing wheel and the third synchronizing wheel have the same number of teeth, and the fourth synchronizing wheel has a smaller number of teeth than the first synchronizing wheel.

7. The auxiliary tensioning feeding device for garment sewing according to claim 2, wherein the tensioning wheel comprises a tensioning wheel body and a tensioning wheel shaft coaxially arranged with the tensioning wheel body, one end of the tensioning wheel shaft is arranged on the tensioning wheel body, and the other end of the tensioning wheel shaft extends outwards; the adjusting mechanism comprises an adjusting slide rail arranged on the bottom plate, an adjusting slide block matched with the adjusting slide rail and a locking nut used for controlling the relative position of the adjusting slide block and the adjusting slide rail, the length direction of the adjusting slide rail is arranged along the length direction of the bottom plate, the tensioning wheel shaft is arranged on the adjusting slide block, and an avoiding groove used for avoiding the tensioning wheel shaft is arranged on the side plate.

8. The auxiliary tensioning feeding device for the garment sewing machine according to claim 7, wherein a threaded hole for matching with the locking nut is formed in the adjusting slide rail, the adjusting slider block comprises a sliding portion and a connecting portion, one end of the connecting portion is arranged on the sliding portion, the other end of the connecting portion extends upwards, and the tensioning wheel shaft is arranged on the connecting portion; the sliding part is matched with the adjusting slide rail, and a kidney-shaped groove for avoiding the locking nut is arranged on the sliding part.

9. The auxiliary tensioning feeding device for the garment sewing machine according to claim 8, wherein the adjusting mechanism further comprises a connecting plate, and the connecting plate is arranged in parallel with the side plate; the upper end of the connecting plate is rotatably connected to the side plate, and the tensioning wheel shaft is mounted at the lower end of the connecting plate through a bearing; the connecting part is provided with an accommodating groove for accommodating the tensioning wheel shaft, and the accommodating groove is vertically arranged; the avoiding groove is an arc-shaped groove corresponding to the moving track of the tensioning wheel shaft.

10. The utility model provides a sewing machine, its characterized in that, includes frame, workstation, sets up sewing machine main part on the workstation and supplementary tensioning material feeding unit of any one of claims 1-9, wherein, sewing machine main part includes frame, aircraft nose and eedle, be equipped with the pushing mechanism who is used for promoting the clothes to go forward on the frame, be equipped with the actuating mechanism who is used for driving eedle reciprocating motion from top to bottom on the aircraft nose.

Technical Field

The invention relates to sewing equipment, in particular to an auxiliary tensioning feeding device for clothing sewing and a sewing machine.

Background

In the textile industry, when the traditional sewing machine is adopted to sew the underpants, if the elastic band is already put into the underpants, a worker needs to sleeve the underpants on the periphery of the frame of the sewing machine for sewing, the underpants are sufficiently tensioned, and if the underpants can move under the driving of the feeding device or the underpants can move under the pulling of the worker, the worker can finish the orderly sewing of a circle on the underpants. When needs make up great underpants, adopt this kind of sewing machine will receive the restriction, because the size of workstation is certain, and the underpants size of making up is not uniform, when the girth of underpants is greater than the girth of workstation, because there is the elastic cord in the underpants, the girth of underpants can change because of the size of pulling power, will influence sutural quality when the speed of sewing up is too fast, for example the axis is inhomogeneous, underpants fold scheduling problem appears, consequently traditional sewing machine's work efficiency is low, the benefit is not good.

In order to solve the problem, the utility model discloses a sewing machine for making scalable underpants which is CN 201400764Y's utility model discloses an authorization bulletin number, including aircraft nose, frame, needle bar, eedle, be provided with the actuating mechanism who is used for driving eedle reciprocating motion in aircraft nose and the frame, the frame outwards extends there is the workstation, the workstation is located the below of eedle, the workstation both sides are provided with the support frame that is used for tensioning underpants respectively, distance between two support frames is adjustable, the support frame includes a floor and the gyro wheel of vertical installation on the floor. When the sewing machine works, the underpants with the elastic bands are sleeved on the rollers of the two support frames, and the distance between the two support frames is adjusted according to the actual size of the underpants, so that the underpants are always kept in a tight state in the sewing process; through setting up the support frame that has adjustable distance, this sewing machine can be applicable to the sewing of not equidimension underpants. However, the above sewing machine still has a problem:

1. in the sewing process, the clothes advance is completed through a pushing mechanism arranged on the machine head, and along the clothes advancing direction, due to the pushing action of the machine head, the part of the clothes from the front roller to the machine head can form large folds due to the accumulation of cloth, so that an operator needs to continuously flatten the clothes in front by hands, the labor is consumed, and the production efficiency is low due to the discontinuity of manual operation.

2. When sewing, when the aircraft nose promotes the clothes and gos forward, very little regional atress on the clothes, in addition the clothes in the front of the aircraft nose is in the state of laxity, in the clothes process of marcing forward, very easily leads to the clothes to deviate to both sides in the process of marcing forward because of the atress is inhomogeneous, leads to sewing quality poor, and the defective percentage increases.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides an auxiliary tensioning feeding device for clothing sewing, which can ensure the smoothness of cloth distributed on the front part and the rear part of a workbench and ensure that the advancing track of the cloth is more straight when underpants with elastic bands are sewn.

The invention also aims to provide a sewing machine with the clothes tensioning and feeding device.

The technical scheme for solving the technical problems is as follows:

an auxiliary tensioning feeding device for clothing sewing comprises a tensioning frame and a roller assembly for tensioning underpants, wherein the roller assembly is arranged on the tensioning frame; the roller assembly comprises a rolling wheel assembly and a tensioning wheel assembly, the rolling wheel assembly is arranged in the advancing direction of clothes and comprises a front rolling wheel located in the front of the workbench, a rear rolling wheel located at the rear of the workbench and a transmission mechanism used for driving the front rolling wheel to follow the rear rolling wheel to rotate, and the tensioning wheel assembly comprises a tensioning wheel located below the workbench and an adjusting mechanism used for adjusting the tensioning wheel to move in the front-rear direction.

The working principle of the auxiliary tensioning feeding device is as follows:

when the underpants with the elastic band are sewn, firstly, the underpants are sleeved on the roller assemblies, the adjusting mechanism is operated according to the sizes of the underpants of different styles, so that the underpants are kept in a tensioning state under the action of the front rolling wheel, the rear rolling wheel and the tensioning wheel, and the upper parts of the underpants are sleeved on the workbench to prepare for sewing operation; then, starting the sewing machine, starting a driving mechanism on the machine head to act, enabling a machine needle to reciprocate up and down under the action of the driving mechanism to sew the underpants, and meanwhile, pushing the underpants forwards by a pushing mechanism on the machine base so as to enable the underpants to rotate around the workbench while sewing; in the process that the pushing mechanism pushes the underpants to move forwards, the underpants drag the rear rolling wheels to rotate, so that the cloth behind the workbench is in a flat state, and the transmission mechanism is used for driving the front rolling wheels to rotate along with the rear rolling wheels, so that the front rolling wheels rotate along with the rear rolling wheels when the underpants drag the rear rolling wheels to rotate, so that the cloth in front of the workbench is driven to move forwards, the cloth in front of the workbench is ensured to be kept in a flat state, namely, the cloth in front of the workbench cannot form folds due to accumulation under the action of the roller components, an operator does not need to constantly level the cloth in front of the workbench by hands, labor force is saved, and the continuity of a sewing process can be ensured, so that the production efficiency is greatly improved; in addition, when pushing mechanism promoted the underpants and moved forward, the underpants dragged the back wheel that rolls and rotates, and under drive mechanism's effect, preceding wheel that rolls is followed and is rotated, like this, the partial front and back atress of underpants on the workstation is balanced, therefore the underpants can keep straight forward advancing in the process of advancing to avoid the unqualified and unattractive problem of quality because of deviating and leading to.

According to a preferable scheme of the invention, the length direction of the tensioning frame is vertical to that of the workbench, the tensioning frame comprises a bottom plate and a side plate arranged on the bottom plate, the side plate stretches across the workbench, and an avoidance space is arranged at the position of the side plate where the workbench is; the front rolling wheel, the rear rolling wheel and the tension wheel are all arranged on the side plates.

According to a preferable scheme of the invention, the front rolling wheel comprises a front rolling wheel body and a front rolling shaft which is coaxially arranged with the front rolling wheel body, one end of the front rolling shaft is connected with one end of the front rolling wheel body, and the other end of the front rolling shaft extends outwards; the rear rolling wheel comprises a rear roller body and a rear rolling shaft which is coaxially arranged with the rear roller body, one end of the rear rolling shaft is connected with one end of the rear roller body, and the other end of the rear rolling shaft extends outwards; the front rolling shaft is arranged in front of the side plate through a bearing, and the rear rolling shaft is arranged behind the side plate through a bearing; the axes of the front rolling shaft and the rear rolling shaft are both vertical to the advancing direction of the clothes.

Preferably, the outer surface of preceding gyro wheel body and the outer surface of back gyro wheel body all are equipped with the annular knurl, the annular knurl is the straight line annular knurl.

Preferably, the highest points of the front roller body and the rear roller body are all flush with the table top of the workbench.

In a preferred embodiment of the present invention, the transmission mechanism includes a first synchronizing wheel disposed on the rear rolling shaft, a second synchronizing wheel mounted on the side plate through a bearing, a third synchronizing wheel mounted on the side plate through a bearing, a fourth synchronizing wheel disposed on the front rolling shaft, a first synchronizing belt, a second synchronizing belt, and a third synchronizing belt, wherein the second synchronizing wheel is disposed below the first synchronizing wheel, the third synchronizing wheel is disposed below the fourth synchronizing wheel, the first synchronizing belt is disposed between the first synchronizing wheel and the second synchronizing wheel, the second synchronizing belt is disposed between the second synchronizing wheel and the third synchronizing wheel, and the third synchronizing belt is disposed between the third synchronizing wheel and the fourth synchronizing wheel.

Preferably, the linear velocity of the front roller wheel is greater than the linear velocity of the rear roller wheel.

Preferably, the first, second and third synchronizing wheels have the same number of teeth, and the fourth synchronizing wheel has a smaller number of teeth than the first synchronizing wheel.

In a preferable scheme of the invention, the tensioning wheel comprises a tensioning wheel body and a tensioning wheel shaft which is coaxial with the tensioning wheel body, one end of the tensioning wheel shaft is arranged on the tensioning wheel body, and the other end of the tensioning wheel shaft extends outwards; the adjusting mechanism comprises an adjusting slide rail arranged on the bottom plate, an adjusting slide block matched with the adjusting slide rail and a locking nut used for controlling the relative position of the adjusting slide block and the adjusting slide rail, the length direction of the adjusting slide rail is arranged along the length direction of the bottom plate, the tensioning wheel shaft is arranged on the adjusting slide block, and an avoiding groove used for avoiding the tensioning wheel shaft is arranged on the side plate.

Preferably, the adjusting slide rail is provided with a threaded hole for matching with the locking nut, the adjusting slide block comprises a sliding part and a connecting part, one end of the connecting part is arranged on the sliding part, the other end of the connecting part extends upwards, and the tensioning wheel shaft is arranged on the connecting part; the sliding part is matched with the adjusting slide rail, and a kidney-shaped groove for avoiding the locking nut is arranged on the sliding part.

Preferably, the adjusting mechanism further comprises a connecting plate, and the connecting plate is arranged in parallel with the side plate; the upper end of the connecting plate is rotatably connected to the side plate, and the tensioning wheel shaft is mounted at the lower end of the connecting plate through a bearing; the connecting part is provided with an accommodating groove for accommodating the tensioning wheel shaft, and the accommodating groove is vertically arranged; the avoiding groove is an arc-shaped groove corresponding to the moving track of the tensioning wheel shaft.

Preferably, the number of the tensioning wheel assemblies is two, and the two tensioning wheel assemblies are respectively arranged in front of the workbench and behind the workbench.

The utility model provides a sewing machine, is in including frame, workstation, setting sewing machine main part on the workstation and supplementary tensioning material feeding unit, wherein, sewing machine main part includes frame, aircraft nose and eedle, be equipped with the pushing mechanism who is used for promoting the clothes to go forward on the frame, be equipped with the actuating mechanism who is used for driving eedle up-and-down motion on the aircraft nose.

Compared with the prior art, the invention has the following beneficial effects:

1. according to the auxiliary tensioning feeding device, the transmission mechanism is arranged between the front rolling wheel and the rear rolling wheel in the rolling wheel assembly, so that the front rolling wheel and the rear rolling wheel rotate, the cloth behind the workbench and the cloth in front of the workbench can be kept in a flat state, an operator does not need to constantly level the cloth in front of the workbench by hands, labor force is saved, continuity of a sewing process can be guaranteed, and production efficiency is greatly improved.

2. According to the auxiliary tensioning feeding device, the front rolling wheel can rotate along with the rear rolling wheel, so that the cloth in front of and behind the workbench can be kept flat, the front and rear stress of the part of the underpants on the workbench is balanced, and the problem that the underpants are off-tracking due to unbalanced stress in the moving process and unqualified and unattractive sewing is avoided.

Drawings

Fig. 1 is a perspective view of the auxiliary tension feeding device of the present invention provided on a sewing machine.

Fig. 2 is a perspective view of one direction of the auxiliary tensioning feeding device.

Fig. 3 is a perspective view of the auxiliary tensioning feeding device in another direction.

Detailed Description

The present invention will be described in further detail with reference to examples and drawings, but the present invention is not limited thereto.

Referring to fig. 1-3, the auxiliary tensioning feeding device for clothing sewing of the invention comprises a tensioning frame 4 and a roller assembly for tensioning the underpants, wherein the roller assembly is arranged on the tensioning frame 4; the roller assembly comprises a rolling wheel assembly and a tensioning wheel assembly, the rolling wheel assembly comprises a front rolling wheel 5 located in front of the workbench 2, a rear rolling wheel 6 located behind the workbench 2 and a transmission mechanism used for driving the front rolling wheel 5 to follow the rear rolling wheel 6 to rotate, and the tensioning wheel assembly comprises a tensioning wheel 7 located below the workbench 2 and an adjusting mechanism used for adjusting the tensioning wheel 7 to move in the front-rear direction.

Referring to fig. 1 to 3, the length direction of the tensioning frame 4 is perpendicular to the length direction of the workbench 2, the tensioning frame 4 includes a bottom plate 8 and a side plate 9 disposed on the bottom plate 8, the side plate 9 spans the workbench 2, and a clearance is disposed at a position where the side plate 9 is located on the workbench 2; the front rolling wheel 5, the rear rolling wheel 6 and the tension wheel 7 are all arranged on the side plate 9.

Referring to fig. 1 to 3, the front rolling wheel 5 includes a front rolling wheel body 5-1 and a front rolling shaft 5-2 coaxially disposed with the front rolling wheel body 5-1, one end of the front rolling shaft 5-2 is connected with one end of the front rolling wheel body 5-1, and the other end extends outwards; the rear rolling wheel 6 comprises a rear roller wheel body 6-1 and a rear rolling shaft 6-2 coaxially arranged with the rear roller wheel body 6-1, one end of the rear rolling shaft 6-2 is connected with one end of the rear roller wheel body 6-1, and the other end extends outwards; the front rolling shaft 5-2 is mounted in front of the side plate 9 through a bearing, and the rear rolling shaft 6-2 is mounted behind the side plate 9 through a bearing; the axes of the front rolling shaft 5-2 and the rear rolling shaft 6-2 are both vertical to the advancing direction of the clothes. The front rolling wheel 5 and the rear rolling wheel 6 are arranged, one end of the front rolling wheel 5 is mounted in front of the side plate 9 through a bearing, one end of the rear rolling wheel 6 is mounted behind the side plate 9 through a bearing, and therefore the front rolling wheel 5 and the rear rolling wheel 6 can smoothly rotate on the side plate 9, and the underpants sleeved on the front rolling wheel 5 and the rear rolling wheel 6 can conveniently rotate.

Referring to fig. 1-3, knurls are arranged on the outer surface of the front roller body 5-1 and the outer surface of the rear roller body 6-1, and the knurls are straight knurls. The front roller body 5-1 and the rear roller body 6-1 are arranged, and the friction force between the front roller body and the cloth of the underpants can be effectively increased by the straight knurling, so that when the cloth drags the rear roller 6 to rotate, the cloth behind the workbench 2 is better in tightening effect due to the larger friction force, and the cloth behind the workbench 2 is smoother; in a similar way, when the front rolling wheel 5 rotates along with the rear rolling wheel 6, and when the front rolling wheel 5 pulls the cloth in front of the workbench 2, the cloth in front of the workbench 2 is tightened better by the larger friction force, so that the cloth in front of the workbench 2 is smoother.

Referring to fig. 1-3, the highest points of the front roller body 5-1 and the rear roller body 6-1 are all flush with the table top of the workbench 2. Therefore, the front rolling wheels 5 and the rear rolling wheels 6 correspond to the height of the workbench 2, when the underpants are sleeved on the roller assemblies, the heights of the workbench 2 and the rear rolling wheels 6 and the cloth between the workbench 2 and the front rolling wheels 5 are the same, and the smoothness is improved.

Referring to fig. 1 to 3, the transmission mechanism includes a first timing pulley 10 provided on the rear rolling shaft 6-2, a second timing pulley 11 mounted on the side plate 9 through a bearing, a third timing pulley 12 mounted on the side plate 9 through a bearing, a fourth timing pulley 13 provided on the front rolling shaft 5-2, a first timing belt 14, a second timing belt 15, and a third timing belt 16, wherein the second synchronizing wheel 11 is positioned below the first synchronizing wheel 10, the third synchronizing wheel 12 is positioned below the fourth synchronizing wheel 13, the first timing belt 14 is provided between the first timing wheel 10 and the second timing wheel 11, the second timing belt 15 is provided between the second timing wheel 11 and the third timing wheel 12, the third timing belt 16 is disposed between the third timing wheel 12 and the fourth timing wheel 13. The working principle of the transmission mechanism is as follows: because the first synchronizing wheel 10 is arranged on the rear rolling shaft 6-2, when the rear rolling wheel 6 rotates, the rear rolling wheel 6 drives the first synchronizing wheel 10 to rotate, and the rotation of the first synchronizing wheel 10 enables the second synchronizing wheel 11 to rotate along with the rotation through the transmission action of the first synchronizing belt 14; the rotation of the second synchronous wheel 11 causes the third synchronous wheel 12 to follow the rotation through the transmission action of the second synchronous belt 15; through the transmission action of the third synchronous belt 16, the fourth synchronous wheel 13 rotates along with the rotation of the third synchronous wheel 12, and the fourth synchronous wheel 13 is arranged on the front rolling shaft 5-2, so that the front rolling wheel 5 rotates along with the rotation of the fourth synchronous wheel 13, and the function that the front rolling wheel 5 rotates along with the rear rolling wheel 6 is realized.

In this embodiment, the linear velocity of the front rolling wheel 5 is greater than the linear velocity of the rear rolling wheel 6. Like this, the effect that preceding rolling wheel 5 drags the cloth that is located 2 the place ahead of workstation is better to further avoid the cloth in 2 the place ahead of workstation to form and pile up, thereby guaranteed that the cloth in 2 the place ahead of workstation is more level and smooth.

Referring to fig. 1 to 3, the first synchronizing wheel 10, the second synchronizing wheel 11 and the third synchronizing wheel 12 have the same number of teeth, and the fourth synchronizing wheel 13 has a smaller number of teeth than the first synchronizing wheel 10. In this way, since the numbers of teeth of the first synchronizing wheel 10, the second synchronizing wheel 11 and the third synchronizing wheel 12 are the same, the rotation of the first synchronizing wheel 10 to the third synchronizing wheel 12 is kept consistent, and the number of teeth of the fourth synchronizing wheel 13 is smaller than that of the first synchronizing wheel 10, so that the linear velocity of the fourth synchronizing wheel 13 is slightly higher than that of the first synchronizing wheel 10, and thus the linear velocity of the front rolling wheel 5 is slightly higher than that of the rear rolling wheel 6.

Referring to fig. 1-3, the tension pulley 7 includes a tension pulley body 7-1 and a tension pulley shaft 7-2 coaxially disposed with the tension pulley body 7-1, one end of the tension pulley shaft 7-2 is disposed on the tension pulley body 7-1, and the other end extends outward; the adjusting mechanism comprises an adjusting slide rail 17 arranged on the bottom plate 8, an adjusting slide block 18 matched with the adjusting slide rail 17 and a locking nut 19 used for controlling the relative position of the adjusting slide block 18 and the adjusting slide rail 17, the length direction of the adjusting slide rail 17 is arranged along the length direction of the bottom plate 8, the tensioning wheel shaft 7-2 is arranged on the adjusting slide block 18, and an avoiding groove 9-1 used for avoiding the tensioning wheel shaft 7-2 is arranged on the side plate 9. The tensioning wheel 7 assembly is arranged, when the trousers with large number of sizes are sewn, the locking nut 19 is firstly loosened, so that the adjusting slide block 18 can freely slide relative to the adjusting slide rail 17; next, dragging the adjusting slide block 18 to enable the adjusting slide block 18 to move in a direction away from the workbench 2, and since the tensioning wheel shaft 7-2 is arranged on the adjusting slide block 18, when the adjusting slide block 18 is moved, the tensioning wheel 7 moves in a direction away from the workbench 2, so that the tensioning effect is achieved on the trousers with large number of sizes; when the trousers with small number of yards are sewn, the same operation is carried out, only the adjusting slide block 18 needs to be moved towards the direction close to the workbench 2, so that the tensioning wheel 7 moves towards the direction close to the workbench 2, and the tensioning effect is achieved on the trousers with small number of yards; therefore, the tensioning wheel set can play a tensioning role on the underpants of different styles by arranging the adjusting mechanism, so that the sewing process is automatically kept flat, the step of manual leveling is omitted, and the working efficiency is greatly improved.

Referring to fig. 1-3, the adjusting slide rail 17 is provided with a threaded hole for matching with the lock nut 19, the adjusting slide block 18 includes a sliding portion 18-1 and a connecting portion 18-2, one end of the connecting portion 18-2 is disposed on the sliding portion 18-1, the other end extends upward, and the tension pulley shaft 7-2 is disposed on the connecting portion 18-2; the sliding part 18-1 is matched with the adjusting slide rail 17, and a kidney-shaped groove for avoiding the locking nut 19 is arranged on the sliding part 18-1. Thus, the locking nut 19 is matched with the threaded hole on the adjusting slide rail 17, and the locking nut 19 is positioned in the kidney-shaped groove, when the locking nut 19 is screwed, the locking nut 19 fixedly connects the sliding part 18-1 to the adjusting slide rail 17, so that the adjusting slide rail 17 is fixed on the adjusting slide rail 17; when the locking nut 19 is loosened, the sliding part 18-1 and the adjusting slide rail 17 can move relatively, so that the position of the adjusting slide rail 17 can be moved, and finally the adjustment of the tension pulley 7 is realized.

Referring to fig. 1-3, the adjusting mechanism further comprises a connecting plate 20, and the connecting plate 20 is arranged in parallel with the side plate 9; the upper end of the connecting plate 20 is rotatably connected to the side plate 9, and the tensioning wheel shaft 7-2 is mounted at the lower end of the connecting plate 20 through a bearing; the connecting part 18-2 is provided with an accommodating groove 18-2-1 for accommodating the tensioning wheel shaft 7-2, and the accommodating groove 18-2-1 is vertically arranged; the avoiding groove 9-1 is an arc-shaped groove corresponding to the moving track of the tensioning wheel shaft 7-2. With the adjusting mechanism with the structure, as the upper end of the connecting plate 20 is rotatably connected to the side plate 9, the lower end of the connecting plate 20 can rotate around the center of the upper end, and the tensioning wheel shaft 7-2 is arranged at the lower end of the connecting plate 20 through a bearing, so that the tensioning wheel 7 can swing around the center of the upper end of the connecting plate 20; the connecting part 18-2 is provided with a containing groove 18-2-1 for containing the tension wheel shaft 7-2, and the containing groove 18-2-1 is arranged along the vertical direction, so when the adjusting slide block 18 is locked on the adjusting slide rail 17 by the locking nut 19, the containing groove 18-2-1 limits the position of the tension wheel shaft 7-2 in the front and back direction, fixes the position of the tension wheel 7, thereby adapting to different sizes of the underpants and playing a role in tensioning the underpants; in addition, set the take-up pulley 7 to the arc orbit removal of upper end wobbling along the connecting plate 20, increased the control range of take-up pulley 7 to can adapt to the making up of more different style underpants.

Referring to fig. 1 to 3, there are two tensioning wheel 7 assemblies, and the two tensioning wheel 7 assemblies are respectively arranged in front of the workbench 2 and behind the workbench 2. Set up two take-up pulley 7 subassemblies, like this, the place ahead and the rear homoenergetic at workstation 2 can play the tensioning effect to the underpants to can increase the scope of adjusting, thereby can adapt to making up of more different style underpants.

Referring to fig. 1-3, the working principle of the auxiliary tensioning feeding device is as follows:

when the underpants with the elastic band are sewn, firstly, the underpants are sleeved on the roller assemblies, the adjusting mechanism is operated according to the sizes of the underpants of different styles, so that the underpants are kept in a tensioning state under the action of the front rolling wheel 5, the rear rolling wheel 6 and the tensioning wheel 7, and the upper parts of the underpants are sleeved on the workbench 2 to prepare for sewing operation; then, starting the sewing machine, starting a driving mechanism on the machine head to act, enabling a machine needle to reciprocate up and down under the action of the driving mechanism to sew the underpants, and meanwhile, pushing the underpants forwards by a pushing mechanism on the machine base so as to enable the underpants to rotate around the workbench 2 while sewing; in the process that the pushing mechanism pushes the underpants to move forwards, the underpants drag the rear rolling wheels 6 to rotate, so that the cloth behind the workbench 2 is in a flat state, and the transmission mechanism is used for driving the front rolling wheels 5 to rotate along with the rear rolling wheels 6, so that the front rolling wheels 5 rotate along with the rear rolling wheels 6 when the underpants drag the rear rolling wheels 6 to rotate, so that the cloth in front of the workbench 2 is driven to move forwards, the cloth in front of the workbench 2 is ensured to be in the flat state, namely, the cloth in front of the workbench 2 cannot form folds due to accumulation under the action of the roller components, an operator does not need to constantly level the cloth in front of the workbench 2 by hands, labor force is saved, and continuity of a sewing process can be ensured, so that production efficiency is greatly improved; in addition, when pushing mechanism promoted the underpants and moved forward, the underpants dragged the back wheel that rolls 6 and rotate, under drive mechanism's effect, preceding wheel 5 that rolls is followed and is rotated, like this, the partial stress balance around of underpants on workstation 2, consequently the underpants can keep straight forward advancing in the process of advancing to avoid the unqualified and unattractive problem of quality because of deviating and leading to.

Referring to fig. 1, a sewing machine comprises a frame 1, a workbench 2, a sewing machine main body arranged on the workbench 2, and the auxiliary tensioning feeding device, wherein the sewing machine main body comprises a machine base, a machine head 3 and a needle, a pushing mechanism for pushing clothes to advance is arranged on the machine base, and a driving machine for driving the needle to reciprocate up and down is arranged on the machine head 3.

The present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents and are included in the scope of the present invention.