阅读说明：本技术 一种缝纫机的抬压脚机构 (Presser foot lifting mechanism of sewing machine ) 是由 李质彬 林高宏 吴文俊 于 2021-02-02 设计创作，主要内容包括：本申请提出一种缝纫机的抬压脚机构,具体涉及缝纫机制造技术领域。包括有送布牙,其特征在于,所述抬压脚机构执行抬压脚动作在送布牙停止前后送布动作的静止状态下进行。抬压脚机构还具有驱动抬压脚凸轮、转动杠杆、抬压脚顶杆、驱动电机和针距定位轮,抬压脚顶杆抵靠在驱动电机驱动抬压脚凸轮具有的抬压脚最高点上时,转动杠杆具有的滑动件位于针距定位轮的针距定位槽中部。本申请送布牙停止前后送布动作的静止状态是基于缝纫机电控系统来控制的,解决了步进电机一拖二的技术下抬压脚动作时送布牙出现抬升动作并高出针板面的技术问题,具有较高推广使用价值。(The application provides a presser foot lifting mechanism of sewing machine, concretely relates to sewing machine manufacturing technical field. The cloth feeding device comprises a feed dog and is characterized in that the presser foot lifting mechanism executes the presser foot lifting action under the static state of the cloth feeding action before and after the feed dog stops. The presser foot lifting mechanism is also provided with a presser foot lifting driving cam, a rotating lever, a presser foot lifting ejector rod, a driving motor and a stitch length positioning wheel, and when the presser foot lifting ejector rod is abutted against the highest point of the presser foot lifting driving cam, which is provided with the presser foot lifting driving cam, the rotating lever is provided with a sliding piece which is positioned in the middle of the stitch length positioning slot of the stitch length positioning wheel. The static state of the cloth feeding action before and after the cloth feeding tooth stops is controlled based on the sewing machine electric control system, the technical problem that the cloth feeding tooth is lifted and is higher than the needle plate surface when the presser foot is lifted under the one-to-two stepping motor technology is solved, and the cloth feeding tooth has high popularization and use values.)

1. A presser foot lifting mechanism of a sewing machine comprises a feed dog (91), and is characterized in that the presser foot lifting mechanism executes the presser foot lifting action under the static state that the feed dog (91) stops the front and back feed actions.

2. The presser foot lifting mechanism of a sewing machine according to claim 1, characterized in that the presser foot lifting mechanism further comprises a driving presser foot lifting cam (22), a rotating lever (41), a presser foot lifting ejector rod (61), a driving motor (10) and a stitch length positioning wheel (21), when the presser foot lifting ejector rod (61) abuts against a presser foot lifting peak (223) of the driving presser foot lifting cam (22) of the driving motor (10), a sliding member (42) of the rotating lever (41) is positioned in the middle of a stitch length positioning groove (212) of the stitch length positioning wheel (21), and the presser foot lifting mechanism performs the presser foot lifting action in a static state that the feed dog (91) stops the front and back feed actions.

3. The presser foot lifting mechanism of a sewing machine according to claim 2, wherein the slider (42) enters the gauge positioning groove (212) from a first return groove (213) provided in the gauge positioning wheel (21) or from a second return groove (214) and pushes the gauge positioning groove (212), and the slider (42) indirectly pushes the swing seat (30).

4. The presser foot lifting mechanism of a sewing machine according to claim 2, wherein the presser foot lifting cam (22) has a presser foot lifting action surface one (221) or a presser foot lifting action surface two (222) which can reach a presser foot lifting peak (223) for the presser foot lifting ram (61), and the presser foot lifting ram (61) returns to a starting point position from the return groove one (213) or from the return groove two (214).

5. The presser foot lifting mechanism of sewing machine according to claim 2, characterized in that the presser foot lifting ejector rod (61) is sleeved in the presser foot lifting mechanism and further comprises a positioning sleeve (62), the presser foot lifting ejector rod (61) is hinged to a presser foot lifting lever (63), the presser foot lifting lever (63) is connected with a presser foot lifting end execution end (64), and the presser foot lifting action is executed by the presser foot lifting end execution end (64).

6. The presser foot lifting mechanism of a sewing machine according to claim 4, wherein the first return groove (213) or the second return groove (214) is used for returning the slider (42) to the needle pitch positioning groove (212) at a positive needle pitch maximum point (215) or a negative needle pitch maximum point (216) of the swing seat (30), and the positive needle pitch maximum point (215) and the negative needle pitch maximum point (216) are located at the end point of the needle pitch adjusting groove (211).

7. The presser foot lifting mechanism of a sewing machine according to claim 2, wherein said gauge positioning groove (212) has an outer circular wall (21b) and an inner circular wall (21c), said slider (42) being slidable between the outer circular wall (21b) and the inner circular wall (21 c).

8. The presser foot lifting mechanism of sewing machine according to claim 2, wherein said driving motor (10) has an output shaft (11) mounting a needle pitch positioning wheel (21), said output shaft (11) and the arc of the needle pitch positioning groove (212) being concentric.

9. The presser foot lifting mechanism of sewing machine according to claim 2, wherein said driving motor (10) performs a presser foot lifting operation within a presser foot lifting corner of the sewing machine.

Technical Field

The application provides a presser foot lifting mechanism of sewing machine, concretely relates to sewing machine manufacturing technical field.

Background

The technical scheme that a stepping motor is used for controlling needle distance adjustment and presser foot lifting action is provided for a sewing machine, mechanical transmission components such as a needle distance adjusting crank and a presser foot lifting crank are mounted on the motor, the needle distance adjusting crank indirectly or directly acts on a swing seat, the acting angles and positions of the stepping motor and the needle distance adjusting crank are adjusted, and therefore the needle distance of the sewing machine is adjusted, then the presser foot lifting action is implemented at different rotating angles by the stepping motor, and the technical effect that the stepping motor drags two is achieved. However, when the sewing machine finishes the action of lifting the presser foot, the feed dog connected with the swinging seat and the feed shaft can perform the action of lifting, which is almost performed simultaneously with the action of lifting the presser foot, so that the condition that the feed dog is lifted to be higher than the surface of the needle plate occurs. The cloth feeding tooth on the surface of the high needle plate can influence the ending of the discharging work of the sewing material, and the sewing material is hooked by the cloth feeding tooth and damaged; secondly, the next sewing operation is adversely affected.

Disclosure of Invention

The presser foot lifting mechanism of the sewing machine is characterized in that the presser foot lifting mechanism executes the presser foot lifting action under the static state of the cloth feeding action before and after the cloth feeding teeth stop.

Further preferably, the presser foot lifting mechanism further comprises a driving presser foot lifting cam, a rotating lever, a presser foot lifting ejector rod, a driving motor and a stitch length positioning wheel, when the presser foot lifting ejector rod abuts against the highest point of the presser foot lifting cam driven by the driving motor, a sliding piece arranged on the rotating lever is positioned in the middle of a stitch length positioning groove of the stitch length positioning wheel, and the presser foot lifting mechanism executes the presser foot lifting action under the static state that the front and back cloth feeding actions of the cloth feeding teeth are stopped.

Preferably, the sliding piece enters the needle distance positioning groove from the first return groove or the second return groove of the needle distance positioning wheel and pushes the needle distance positioning groove, and the sliding piece indirectly pushes the swinging seat.

Preferably, the presser foot lifting cam has a presser foot lifting action surface I or a presser foot lifting action surface II, which can reach the highest point of the presser foot lifting rod, and the presser foot lifting rod returns to the starting point position from the first return groove or the second return groove.

Preferably, the presser foot lifting ejector rod is sleeved in the presser foot lifting mechanism and is further provided with a positioning sleeve, the presser foot lifting ejector rod is hinged with a presser foot lifting lever, the presser foot lifting lever is connected with the presser foot lifting tail execution end, and then the presser foot lifting action is executed by the presser foot lifting tail execution end.

Preferably, the first return groove or the second return groove is used for returning the sliding part to the needle pitch positioning groove at a positive needle pitch maximum point or a negative needle pitch maximum point of the swinging seat, and the positive needle pitch maximum point and the negative needle pitch maximum point are positioned at the tail end point of the needle pitch adjusting groove.

Preferably, the gauge positioning slot has an outer circular wall and an inner circular wall, the slider sliding between the outer circular wall and the inner circular wall.

Preferably, the driving motor is provided with an output shaft which is provided with a needle pitch positioning wheel, and the output shaft and the circular arc of the needle pitch positioning groove are positioned on a concentric circular arc.

Preferably, the driving motor performs a presser foot lifting action within a presser foot lifting corner of the sewing machine.

The presser foot lifting mechanism of the sewing machine performs the presser foot lifting action under the static state of the cloth feeding action before and after the cloth feeding tooth stops; when the presser foot lifting ejector rod is abutted against the presser foot lifting highest point of the presser foot lifting cam driven by the driving motor, the sliding piece of the rotating lever is positioned in the middle of the needle distance positioning groove of the needle distance positioning wheel, and the presser foot lifting mechanism of the sewing machine performs the presser foot lifting action in the same way. The static state of the cloth feeding action before and after the cloth feeding teeth stop is controlled based on the sewing machine electric control system, the presser foot lifting action is executed by the presser foot lifting mechanism of the sewing machine under the static state of the cloth feeding action before and after the cloth feeding teeth stop, the technical problem that the cloth feeding teeth are lifted and higher than the needle plate surface when the presser foot lifting action is carried out under the one-to-two stepping motor technology is solved, and the cloth feeding mechanism has high popularization and use values.

Drawings

FIG. 1 is a structural view of a presser foot lifting mechanism of a sewing machine according to the present application;

FIG. 2 is a schematic view of a feed dog gauge positioning wheel and gauge adjustment of a presser foot lifting mechanism of a sewing machine according to the present application;

FIG. 3 is a schematic view of a needle gauge adjustment and swing seat of a presser foot lifting mechanism of a sewing machine according to the present application;

FIG. 4 is a schematic view of a stitch length adjustment slot of a presser foot lifting mechanism of a sewing machine according to the present application;

FIG. 5 is a side view of a combination wheel of a presser foot lifting mechanism of a sewing machine according to the present application;

FIG. 6 is a schematic view of a stitch length dial bar of a presser foot lifting mechanism of a sewing machine according to the present application;

FIG. 7 is a thread trimming structure view of a presser foot lifting mechanism of a sewing machine according to the present application;

FIG. 8 is a schematic view of a presser foot lifting cam of a presser foot lifting mechanism of a sewing machine according to the present application.

Reference numerals: the device comprises a driving motor 10, an output shaft 11, a shaft hole 12, a combination wheel 20, a needle pitch positioning wheel 21, a needle pitch adjusting groove 211, a needle pitch positioning groove 212, an outer circular wall 21b, an inner circular wall 21c, a first return groove 213, a second return groove 214, a maximum positive needle pitch point 215, a maximum negative needle pitch point 216, a presser foot lifting cam 22, a presser foot lifting action surface one 221, a presser foot lifting action surface two 222, a presser foot lifting peak 223, an idle surface 224, a trimming crank wheel 23, a rotating column 231, a swinging seat 30, a feeding swinging plate 31, a long swinging plate 33, a feeding short swinging plate 32, a rotating lever 41, a sliding part 42, a lever supporting shaft 43, a connecting rod 44, a machine body 45, a cloth feeding shaft 51, a cloth feeding crank 52, a swinging connecting rod 53, a presser foot lifting ejector rod 61, a positioning sleeve 62, a presser foot lever 63, a presser foot end lifting execution end 64, a trimming fork wheel 71, a fixed shaft 72, a trimming action surface 73, a trimming return action, a trimming connecting rod 75, a trimming long shaft 76, a main shaft motor 81 and a cloth feeding tooth 91.

Detailed Description

Preferred embodiments of the present application will be described in detail below with reference to fig. 1 to 8, so that the advantages and features of the present application can be more easily understood by those skilled in the art, and the scope of protection of the present application will be clearly and clearly defined, and these embodiments are only for illustrating the present invention and are not limited thereto.

The application provides a presser foot lifting mechanism of a sewing machine, the sewing machine is provided with a stitch length adjusting mechanism, a presser foot lifting mechanism, a thread trimming mechanism and a driving motor 10, and the stitch length adjusting mechanism is provided with a stitch length positioning wheel 21, a rotating lever 41 and a feed dog 91. The output shaft 11 of the driving motor 10 is provided with a combination wheel 20, and the combination wheel 20 is used for realizing the needle pitch adjusting action, the action of positioning the feed dog to stop the front and back feed, the action of lifting the presser foot and the thread trimming action of the sewing machine at different time periods. The four sewing actions are at each driving corner of the driving motor 10, and the wheels with different functions of the combined wheel 20 are driven by the driving motor 10 in each driving corner to complete the four sewing actions, or complete any one of the four sewing actions, or randomly combine two or more than two sewing actions.

The combination wheel 20 has three functional wheels, namely a stitch length positioning wheel 21, a pressure lifting and pressing foot cam 22 and a thread trimming crank wheel 23, the stitch length positioning wheel 21, the pressure lifting and pressing foot cam 22 and the thread trimming crank wheel 23 are integrally combined into the combination wheel 20, the three functional wheels can be independently arranged and respectively installed and fixed on the output shaft 11, and the pressure lifting and pressing foot cam 22 is positioned between the stitch length positioning wheel 21 and the thread trimming crank wheel 23 no matter the combination or the independent arrangement. The combination wheel 20 has a shaft hole 12 through which the output shaft 11 can be inserted and positioned, and the combination wheel 20 is fitted and fixed to the output shaft 11, so that the output shaft 11 is provided with the pitch positioning wheel 21. The output shaft 11 and the circular arc of the needle pitch positioning groove 212 are positioned on a concentric circular arc.

The pitch wheel 21 has a pitch adjustment groove 211, a pitch positioning groove 212, a first return groove 213, and a second return groove 214. The two ends of the needle pitch adjusting groove 211 adjacent to the needle pitch positioning groove 212 are a first return groove 213 and a second return groove 214, respectively. The needle pitch adjusting groove 211 is correspondingly matched with the rotating lever 41, the working movable fulcrum of the rotating lever 41 is the sliding part 42, the sliding part 42 is positioned in the middle of the rotating lever 41, the sliding part 42 slides and works among the needle pitch adjusting groove 211, the needle pitch positioning groove 212, the first return groove 213 and the second return groove 214 according to sewing actions, and the first return groove 213 or the second return groove 214 is used for returning the sliding part 42 to the needle pitch positioning groove 212 at the positive needle pitch maximum point 215 or the negative needle pitch maximum point 216 of the swinging seat 30. The maximum point 215 of the positive needle pitch and the maximum point 216 of the negative needle pitch of the swing seat 30 are located at the end points of both ends of the needle pitch adjusting groove 211, and the maximum point 215 of the positive needle pitch and the maximum point 216 of the negative needle pitch are uncertain and can be interchanged due to different models of sewing machines. One end of the rotating lever 41 is sleeved on the lever supporting shaft 43, the lever supporting shaft 43 is positioned on the machine body 45, and the lever supporting shaft 43 plays a role in fixing the rotating shaft by rotating the lever 41. The other end of the rotating lever 41 is hinged with a connecting rod 44, and the other end of the connecting rod 44 is hinged with the swinging seat 30. The stitch length adjustment is to rotate the stitch length positioning wheel 21 by a certain angle by the driving motor 10 to change the action position of the sliding part 42 in the stitch length adjusting groove 211, that is, the stitch length adjusting groove 211 pushes the sliding part 42, and then the original swing angle of the swing seat 30 is changed by rotating the lever 41 and the connecting rod 44, so as to realize the stitch length adjustment. The stitch length adjustment is performed in a state where the sewing machine is stopped, and the stitch length after the adjustment is successful is given to the swing base 30 as a new fixed stitch length.

When the thread cutting is required after the sewing is finished, the sliding member 42 is separated from the stitch length adjusting groove 211 and passes through the first return groove 213 or the second return groove 214 to enter the stitch length positioning groove 212 under the condition that the driving motor 10 drives the stitch length positioning wheel 21. The stitch length positioning groove 212 has an outer circular wall 21b and an inner circular wall 21c, the slider 42 slides between the outer circular wall 21b and the inner circular wall 21c, when the slider 42 enters the stitch length positioning groove 212, the stationary position of the feed dog 91 stopping the front and rear cloth feeding actions is indirectly determined, and the sewing machine can perform thread cutting under the cloth feeding stopping action, thereby realizing the technical effect of almost no residual thread. When the needle pitch positioning wheel 21 rotates, the sliding member 42 enters the needle pitch positioning groove 212 from the needle pitch adjusting groove 211, the sliding member 42 together with the rotating lever 41 pushes the feeding swing plate 31 of the swing base 30 through the connecting rod 44, so that the feeding long swing plate 33 and the feeding short swing plate 32 of the swing base 30 are pushed to a flush state, the feeding long swing plate 33 and the feeding short swing plate 32 in the flush state are driven by the spindle motor 81, and the swing connecting rod 53 acts on the swing base 30 to make the swing angle zero, that is, the needle pitch is zero. The feed crank 52 is fixed to the feed shaft 51 and hinged to the swing base 30, the feed shaft 51 is indirectly connected to the feed dog 91, and the feed crank 52 connecting the swing base 30 and the feed shaft 51 does not swing when the swing angle of the swing base 30 is zero, and at this time, the swing base 30 does not provide a swing source for the forward and backward movement of the feed dog 91, so that the feed shaft 51 does not swing, and the feed dog 91 does not perform the forward and backward feed movement. The method realizes the gist of the invention by determining the cloth feeding stopping action of the cloth feeding dog 91 of the sewing machine, and the sewing machine immediately executes the thread cutting action after determining the cloth feeding stopping action of the cloth feeding dog 91, thereby achieving the technical effect of realizing no residual thread in the thread cutting of the sewing machine.

The above-described thread trimming operation is performed after the slider 42 enters the pitch positioning groove 212 from the first return groove 213 or the second return groove 214 and pushes the pitch positioning groove 212, that is, the presser foot lifting operation is performed in a stationary state in which the front and rear feed operations of the feed dog 91 are stopped, and the presser foot lifting operation is performed after the thread trimming operation is completed.

When the sliding member 42 in the needle pitch positioning wheel 21 starts to enter the needle pitch positioning groove 212 and pushes the connecting rod 44 to indirectly make the feeding long swinging plate 33 and the feeding short swinging plate 32 flush, the rotating column 231 of the thread cutting crank wheel 23 applies a pushing force to the thread cutting acting surface 73 of the thread cutting fork wheel 71 in the thread cutting corner of the driving motor 10, and then the thread cutting acting surface 73 pushes the thread cutting long shaft 76 and the thread cutting action is executed by the last thread cutting executing end. The thread cutting long shaft 76 is hinged to the thread cutting connecting rod 75 through a passage and penetrates through the whole machine body 45 at the end thread cutting executing end, namely, the thread cutting connecting rod 75 drives the thread cutting long shaft 76 from the thread cutting connecting rod 75 to the end thread cutting executing end 77.

The thread cutting fork wheel 71 is positioned on the fixed shaft 72 by using the fixed shaft 72 as a rotating shaft, and a thread cutting action surface 73 and a thread cutting return action surface 74 of the thread cutting fork wheel 71 are pushed by the rotating column 231 to rotate along with the fixed shaft 72. The thread cutting action surface 73 is hinged to the thread cutting connecting rod 75, the thread cutting action surface 73 is stressed to push the thread cutting connecting rod 75 to press downwards, the thread cutting connecting rod 75 pushes the thread cutting end execution end 76 to execute thread cutting action, and thread cutting under a static state that the front and back cloth feeding actions of the cloth feeding teeth 91 are stopped is achieved.

The rotating column 231 is located between the trimming acting surface 73 and the trimming returning acting surface 74, the rotating column 231 is located in the idle stroke between the trimming acting surface 73 and the trimming returning acting surface 74, and the needle pitch positioning wheel 21 is driven by the spindle motor 81 through the swinging connecting rod 53 to idle in the idle stroke during normal sewing, so that the driving motor 10 cannot generate actual action on trimming during normal sewing of the sewing machine of the application, and the rotating column 231 cannot touch the trimming acting surface 73 and the trimming returning acting surface 74 during other actions. The thread cutting return action surface 74 is used for returning the thread cutting fork wheel 71 to the original position of thread cutting after thread cutting, when the rotating column 231 presses the thread cutting action surface 73, that is, the rotating column 231 rotates for one circle, not only thread cutting is performed, but also the integral return of the thread cutting fork wheel 71 is completed.

When the sliding member 42 inside the stitch length positioning wheel 21 enters the stitch length positioning groove 212 to complete the thread trimming operation, the sewing machine immediately performs the presser foot lifting operation. The presser foot lifting cam 22 has a first presser foot lifting action surface 221, a second presser foot lifting action surface 222 and an idle surface 224, and a presser foot lifting peak 223 is formed between the first presser foot lifting action surface 221 and the second presser foot lifting action surface 222. During thread trimming, the presser foot lifting push rod 61 abuts against the idle surface 224 of the presser foot lifting cam 22, so that the sewing machine normal sewing and thread trimming operation driving motor 10 does not have an actual operation effect on the presser foot lifting.

The drive motor 10 performs a presser foot raising operation within the presser foot raising corner. The presser foot lifting mechanism is provided with a presser foot lifting cam 22 and a needle pitch positioning wheel 21, the driving motor 10 drives the presser foot lifting cam 22 to lift the presser foot lifting ejector rod 61, the sliding piece 42 can enter and push the needle pitch positioning groove 212 from the first return groove 213 or the second return groove 214, and the presser foot lifting action under the static state position that the front and back cloth feeding actions of the cloth feeding dog 91 are stopped is realized, in other words, when the static state that the front and back cloth feeding actions of the cloth feeding dog 91 are stopped is the zero position of the swing seat 30, the sewing machine is the zero needle pitch when the swing seat 30 is at the zero position, and the cloth feeding dog 91 does not have the front and back cloth feeding swing angle. The feed dog 91 is located at the original position below the needle plate, and naturally located below the needle plate without the swing angle of the front and rear feed. The first presser action surface 221 or the second presser action surface 222 of the presser cam 22 can reach the presser peak 223 for the presser lift ram 61, and the presser lift ram 61 can return to the starting position from the first return groove 213 or the second return groove 214. The presser foot lifting ejector rod 61 is sleeved in the positioning sleeve 62, the presser foot lifting ejector rod 61 is hinged with the presser foot lifting lever 63, the presser foot lifting lever 63 is connected with the presser foot lifting end execution end 64, the presser foot lifting action is executed by the presser foot lifting end execution end 64, and the presser foot lifting action at the static state position of the front and back cloth feeding actions of the cloth feeding teeth 91 is realized through the presser foot lifting action, so that the technical value is high.

The above description is only a preferred embodiment of the present application, and not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the specification and the drawings of the present application, or which are directly or indirectly applied to other related technical fields, are also included in the scope of the present application.