Stitch length adjusting device of sewing machine and sewing machine

Abstract

The utility model provides a stitch length adjusting device of a sewing machine and the sewing machine, and relates to the technical field of sewing. The needle pitch adjusting device comprises a rack, a main driving mechanism, a pitch adjusting driving mechanism and a feeding mechanism, the main driving mechanism is arranged on the rack and comprises an eccentric transmission assembly and a locking assembly, the eccentric transmission assembly can rotate relative to the rack, the locking assembly and the eccentric transmission assembly are switched between a locking state and an unlocking state, and the pitch adjusting driving mechanism is arranged on the rack. In the locking state, the eccentric transmission assembly has a first eccentricity degree, and in the unlocking state, the eccentric transmission assembly has a second eccentricity degree. The distance adjusting driving mechanism is arranged on the rack and is in transmission fit with the locking assembly so as to drive the eccentric transmission assembly to be switched between the locking state and the unlocking state. The feeding mechanism is movably arranged on the rack and is in transmission connection with the eccentric transmission assembly. According to the stitch length adjusting device of the sewing machine and the sewing machine, automatic adjustment of the stitch length can be achieved, and the operation efficiency of the sewing machine is guaranteed.

Description

TECHNICAL FIELD

[0001] The utility model relates to sewing technical field especially, relate to a needle spacing adjusting device and sewing machine of sewing machine. BACKGROUND

[0002] Sewing machine (Sewing machine) is with one or more sewing line, on the seam, form one or more line, make one layer or more seam interlace or sew up the machine.

[0003] Sewing machine needs to adjust the needle spacing according to actual use demand in the sewing process, the existing sewing machine usually needs to be adjusted by manual operation when adjusting the needle spacing size, and the steps are tedious, and often need to be adjusted for many times due to inaccurate adjustment, influence operation efficiency. UTILITY MODEL CONTENTS

[0004] In view of above problem, the present application provides a needle spacing adjusting device and sewing machine of sewing machine, can realize the automatic adjustment of needle spacing, guarantee operation efficiency.

[0005] One aspect of the present application provides a needle spacing adjusting device of sewing machine, comprising:

[0006] Rack;

[0007] Main drive mechanism, be located in the rack, the main drive mechanism includes: eccentric transmission assembly and locking assembly, the eccentric transmission assembly is rotatable relative to the rack, the locking assembly and the eccentric transmission assembly switch between the locking state and the unlocking state, in the locking state, the eccentric transmission assembly has the first eccentricity, in the unlocking state, the eccentric transmission assembly has the second eccentricity;

[0008] Distance adjusting drive mechanism, be located in the rack, and with the locking assembly transmission cooperation, to drive the eccentric transmission assembly switch between the locking state and the unlocking state;

[0009] Feeding mechanism, movably be located in the rack, and with the eccentric transmission assembly transmission connection.

[0010] In a possible implementation manner, the locking assembly includes locking sheet, the locking sheet has first position and second position, the locking sheet is configured, when the first position, the eccentric transmission assembly is the locking state, when the second position, the eccentric transmission assembly is the unlocking state;

[0011] The distance adjusting drive mechanism and the locking sheet transmission cooperation, to make the eccentric transmission assembly switch between the locking state and the unlocking state.

[0012] In a possible implementation manner, the distance adjusting drive mechanism includes:

[0013] a first push rod movably arranged on the frame along the sliding direction of the locking piece, a free end of the first push rod being separably connected with the locking piece to push the locking piece to move along a preset track or to be separated from the locking piece;

[0014] a driving device, comprising a second driving member fixedly arranged on the frame and a transmission shaft rotatably supported on the frame and perpendicular to the extending direction of the first push rod, the transmission shaft being provided with a first curved member, a peripheral wall of the first curved member being provided with a driving protrusion, the driving protrusion being adapted to push the first push rod to move when the first curved member rotates with the transmission shaft.

[0015] In a possible implementation, the locking piece is further connected with a first elastic return member, the first elastic return member being configured to apply an acting force to the locking piece in a direction opposite to the pushing direction of the first push rod, i.e., to push the locking piece to move towards the first position; and / or,

[0016] the distance adjusting driving mechanism further comprises a second elastic return member, the second elastic return member being sleeved on the first push rod, the second elastic return member being connected with the first push rod and the frame respectively, the second elastic return member being configured to apply an acting force to the first push rod in a direction opposite to the pushing direction of the first curved member.

[0017] In a possible implementation, the main driving mechanism further comprises a first driving member, a main shaft and a lifting shaft sleeve, one end of the main shaft being connected with the first driving member, the other end of the main shaft penetrating through the lifting shaft sleeve and being rotatable relative to the lifting shaft sleeve, the eccentric transmission assembly being arranged on the part of the main shaft penetrating through the lifting shaft sleeve;

[0018] the eccentric transmission assembly comprises:

[0019] a stitch length adjusting seat sleeved on the main shaft and fixedly connected with the main shaft, one side of the stitch length adjusting seat away from the lifting shaft sleeve being provided with a connecting pin, the connecting pin being eccentrically arranged with the main shaft;

[0020] a feed eccentric wheel being provided with a first assembly hole and a second assembly hole, the first assembly hole being eccentrically arranged, an inner diameter of the first assembly hole being greater than an outer diameter of the main shaft, the main shaft penetrating through the first assembly hole and defining an assembly gap with an inner wall of the first assembly hole, the connecting pin penetrating through the second assembly hole;

[0021] a connecting rod, a first end of the connecting rod being connected with the feed eccentric wheel, a second end of the connecting rod being drivingly connected with the feeding mechanism.

[0022] In a possible implementation, the needle spacing adjusting seat comprises a seat body portion and a transmission portion arranged in sequence along the axial direction of the main shaft, the seat body portion is fixedly connected with the main shaft, and the connecting pin is arranged on the side of the transmission portion away from the seat body portion;

[0023] The fabric feeding eccentric wheel comprises a first main body portion and a first shaft sleeve portion arranged in sequence along the axial direction of the main shaft, the outer diameter of the first shaft sleeve portion is smaller than the outer diameter of the first main body portion, the second assembly hole is arranged on the edge of the first main body portion, the first assembly hole penetrates the first main body portion and the first shaft sleeve portion in sequence, the first end of the connecting rod is sleeved on the outside of the first shaft sleeve portion, and the connecting rod abuts against the first main body portion.

[0024] In a possible implementation, the locking assembly further comprises:

[0025] A needle spacing adjusting cam is sleeved on the main shaft and arranged eccentrically relative to the main shaft, the needle spacing adjusting cam comprises a second main body portion and a second shaft sleeve portion, the second shaft sleeve portion is located on the side of the second main body portion facing the fabric feeding eccentric wheel, the second shaft sleeve portion penetrates the installation gap, the connecting rod abuts against the second main body portion, and the side of the second main body portion away from the second shaft sleeve portion is provided with a sliding rail,

[0026] The locking piece is movably arranged on the sliding rail, the locking piece is provided with a locking rack, the locking piece is provided with an avoiding hole extending along the length direction of the sliding rail, and the main shaft penetrates the avoiding hole;

[0027] An outer tooth seat is sleeved on the main shaft and fixedly connected with the main shaft, the outer periphery of the outer tooth seat is provided with a matching tooth, and the matching tooth is engaged with the locking rack along the extension direction of the sliding rail;

[0028] The distance adjusting driving mechanism is in driving cooperation with the locking piece to drive the outer tooth seat to move along the sliding rail.

[0029] In a possible implementation, one of the inner wall of the first shaft sleeve portion and the outer wall of the second shaft sleeve portion is provided with a limiting key, and the other is provided with a key groove, and the limiting key is engaged in the key groove.

[0030] In a possible implementation, the feeding mechanism comprises:

[0031] A tooth frame is movably arranged on the tooth lifting shaft sleeve along the radial direction of the main shaft, the tooth frame has a first assembly end and a second assembly end opposite along the moving direction of the tooth frame;

[0032] A fabric feeding tooth is arranged on the first assembly end;

[0033] The second curved member is rotatably arranged at the second assembly end, and the second end of the connecting rod is connected with the second curved member and drives the second curved member to move synchronously.

[0034] In a possible implementation, the second end of the connecting rod is provided with a first pin hole, and the second curved member is provided with a second pin hole.

[0035] The feeding mechanism further comprises a differential curved member provided with a third pin hole and a fourth pin hole, the first pin hole and the third pin hole are connected through a first pin shaft, and the second pin hole and the fourth pin hole are connected through a second pin shaft.

[0036] The sewing machine further comprises the stitch spacing adjustment device of any of the possible implementations.

[0037] The stitch spacing adjustment device of the sewing machine and the sewing machine, when the stitch spacing needs to be adjusted, input the stitch spacing value in the electric control operation panel, the control system automatically operates the pitch adjustment driving mechanism, the locking assembly is switched from the locking state to the unlocking state, then the eccentric transmission assembly realizes the adjustment of the eccentricity by changing from the first eccentricity to the second eccentricity, and the moving track of the feeding mechanism is changed, the feeding mechanism reciprocates according to the new moving track, and the stitch spacing adjustment of the sewing machine is realized. The automatic adjustment of the stitch spacing is realized through the pitch adjustment driving mechanism, the tediousness and errors of manual operation are avoided, in addition, the design of the locking assembly and the eccentric transmission assembly ensures the accuracy of the stitch spacing adjustment, reduces the number of repeated adjustments, and improves the work efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0039] Figure 1 It is an angle structure diagram of the stitch spacing adjustment device of the sewing machine of the present application.

[0040] Figure 2 It is a partial structure diagram of the stitch spacing adjustment device of the sewing machine of the present application.

[0041] Figure 3 It is an explosion view of the partial structure of the stitch spacing adjustment device of the sewing machine of the present application.

[0042] Figure 4Another angle of the structure of the stitch length adjusting device of the sewing machine according to the embodiment of the present application;

[0043] Figure 5 For Figure 3 Structure diagram of the stitch length adjusting cam.

[0044] Explanation of reference numerals:

[0045] 100 - frame;

[0046] 200 - main driving mechanism; 210 - first driving member; 220 - main shaft; 230 - lifting shaft sleeve;

[0047] 240 - eccentric transmission assembly; 241 - stitch length adjusting seat; 242 - connecting pin; 243 - cloth feeding eccentric wheel; 2431 - first main body part; 2432 - first shaft sleeve part; 244 - connecting rod;

[0048] 250 - stitch length adjusting cam; 251 - second main body part; 2511 - slide rail; 2512 - first elastic reset member; 2513 - insertion slot; 252 - second shaft sleeve part; 253 - locking piece; 2531 - locking rack; 254 - outer tooth seat; 2541 - matching tooth;

[0049] 260 - bearing member;

[0050] 300 - feeding mechanism; 310 - tooth rack; 311 - first assembly end; 312 - second assembly end; 320 - cloth feeding tooth; 330 - second curved member; 340 - differential curved member; 350 - first pin shaft; 360 - second pin shaft;

[0051] 400 - stitch length adjusting driving mechanism; 410 - first push rod; 420 - driving device; 421 - second driving member; 422 - transmission shaft; 423 - first curved member; 4231 - driving convex part; 430 - second elastic reset member; 440 - sealing ring;

[0052] 500 - electric control system;

[0053] 600 - transmitting sensor;

[0054] 700 - receiving sensor. DETAILED DESCRIPTION

[0055] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0056] Sewing machine is a machine that uses one or more sewing threads to form one or more stitches on the sewing material, interweave or sew one or more layers of the sewing material, and can be divided into household sewing machines, industrial sewing machines, multifunctional sewing machines, etc., and is widely used in families, garment factories, hat and shoe factories, etc. and is one of indispensable equipment in the textile industry.

[0057] The sewing machine needs to adjust the stitch length according to the actual use requirement during the sewing process. The existing sewing machine usually needs to be manually operated when adjusting the size of the stitch length, which is tedious and difficult to achieve the accurate value at one time. There are visual errors, hand feeling differences and other factors in the adjustment process, and the operator may need to adjust repeatedly to approach the target stitch length, which affects the work efficiency.

[0058] Therefore, the utility model provides a kind of stitch length adjusting device and sewing machine of sewing machine, when needing to adjust stitch length, second drive piece starts, second drive piece drives transmission shaft rotation, the rotation of transmission shaft drives first crank member rotation, in the rotation process, the drive convex part on first crank member is contacted with first push rod, and first push rod is moved along slide rail, first push rod cancels the meshing state of locking rack and matching tooth, eccentric transmission assembly is in the unlocking state, and then carry out stitch length adjustment, specifically, first drive piece is started to operate, to drive main shaft low-speed rotation, main shaft rotates preset angle to make eccentric transmission assembly change from first eccentricity to second eccentricity, since the feed eccentric wheel is matched with eccentric transmission assembly, the feed eccentric wheel rotates along connecting pin, the feed eccentric wheel reaches preset eccentric position, so that the swing amplitude of connecting rod changes, i.e. the advancing speed of feed dog changes, stitch length adjustment is completed, avoids the tedious and error of manual operation, reduces the number of repeated adjustments, improves work efficiency.

[0059] The following will be described in combination with Figures 1-4 The stitch length adjusting device of the sewing machine of the first aspect embodiment of the present application is described.

[0060] In combination with Figure 1 And Figure 3 The stitch length adjusting device of the sewing machine of the present embodiment includes a rack 100, a main drive mechanism 200, a feeding mechanism 300 and a pitch adjusting drive mechanism 400.

[0061] The main driving mechanism 200 is arranged on the frame 100, and the main driving mechanism 200 comprises a first driving member 210, a main shaft 220, a lifting shaft sleeve 230, an eccentric transmission assembly 240 and a locking assembly. One end of the main shaft 220 is connected with the first driving member 210, and the other end penetrates through the lifting shaft sleeve 230 and is rotatable relative to the lifting shaft sleeve 230. The eccentric transmission assembly 240 is arranged on the part of the main shaft 220 penetrating through the lifting shaft sleeve 230. The locking assembly is switched between a locking state and an unlocking state with the eccentric transmission assembly 240. In the locking state, the eccentric transmission assembly 240 has a first eccentricity. In the unlocking state, the eccentric transmission assembly 240 has a second eccentricity.

[0062] The lifting shaft sleeve 230 is fixed on the frame 100, and the main shaft 220 penetrates through the lifting shaft sleeve 230 and is rotatable relative to the lifting shaft sleeve 230, so as to provide a mounting space for the eccentric transmission assembly 240. The eccentric transmission assembly 240 is arranged on the main shaft 220, and the moving track of the feeding mechanism 300 is changed by changing the eccentric distance of the eccentric transmission assembly 240, so as to affect the stitch length. The locking assembly cooperates with the eccentric transmission assembly 240 to control the change of the eccentric distance, so as to realize the two states of locking and unlocking.

[0063] The feeding mechanism 300 is movably arranged on the lifting shaft sleeve 230 along the radial direction of the main shaft 220 and is in driving connection with the eccentric transmission assembly 240. The stitch length adjusting driving mechanism 400 is arranged on the frame 100 and is in driving cooperation with the locking assembly, so as to drive the eccentric transmission assembly to be switched between the locking state and the unlocking state. The feeding mechanism 300 is driven by the eccentric transmission assembly 240 to realize the reciprocating movement along the radial direction, so as to drive the stitch length adjustment of the sewing machine. The stitch length adjusting driving mechanism 400 drives the locking assembly to be switched between the locking state and the unlocking state, so as to change the eccentric distance of the eccentric transmission assembly 240 and realize the accurate adjustment of the stitch length.

[0064] It can be seen that when the stitch length needs to be adjusted, the electric control system 500 automatically operates the stitch length adjusting driving mechanism 400, so that the locking assembly is switched from the locking state to the unlocking state. Then, the eccentric transmission assembly 240 realizes the adjustment of the eccentricity by changing from the first eccentricity to the second eccentricity, so as to cause the change of the moving track of the feeding mechanism 300. The feeding mechanism 300 reciprocates according to the new moving track, so as to realize the stitch length adjustment of the sewing machine. The automatic adjustment of the stitch length is realized by the stitch length adjusting driving mechanism 400, which avoids the tediousness and error of manual operation. In addition, the design of the locking assembly and the eccentric transmission assembly 240 ensures the accuracy of the stitch length adjustment, reduces the number of repeated adjustments, and improves the work efficiency.

[0065] In some embodiments, in combination with Figure 2 , Figure 3 and Figure 4 , the eccentric transmission assembly 240 comprises a stitch length adjusting seat 241, a cloth feeding eccentric wheel 243 and a connecting rod 244.

[0066] The needle pitch adjusting seat 241 is sleeved on the main shaft 220 and fixedly connected with the main shaft 220. One side of the needle pitch adjusting seat 241 away from the lifting tooth shaft sleeve 230 is provided with a connecting pin 242. The connecting pin 242 is eccentrically arranged with the main shaft 220. In this way, the axis of the connecting pin 242 does not coincide with the axis of the main shaft 220, but deviates by a certain distance, realizing eccentricity.

[0067] The fabric feeding eccentric wheel 243 is provided with a first assembly hole and a second assembly hole. The first assembly hole is eccentrically arranged. The inner diameter of the first assembly hole is larger than the outer diameter of the main shaft 220. The main shaft 220 is arranged in the first assembly hole and defines an assembly gap with the inner wall of the first assembly hole. The connecting pin 242 is arranged in the second assembly hole.

[0068] In this way, when the fabric feeding eccentric wheel 243 is sleeved on the main shaft 220, an assembly gap is defined between the two, which allows the fabric feeding eccentric wheel 243 to have a certain floating range on the main shaft 220, so as to change the eccentric position when rotating. The matching mode of the first assembly hole and the main shaft 220 allows the fabric feeding eccentric wheel 243 to rotate with the main shaft 220, but can also eccentrically move relative to the main shaft 220 within a predetermined range. The second assembly hole is used to arrange the connecting pin 242. The connecting pin 242 connects the needle pitch adjusting seat 241 and the fabric feeding eccentric wheel 243, so that an eccentric relationship is formed between the two.

[0069] The first end of the connecting rod 244 is connected with the fabric feeding eccentric wheel 243, and the second end is drivingly connected with the feeding mechanism 300. In this way, when the fabric feeding eccentric wheel 243 rotates and eccentrically moves with the main shaft 220, the connecting rod 244 transmits the movement to the feeding mechanism 300.

[0070] It can be seen that the eccentric transmission assembly 240 realizes the adjustment of the movement track of the feeding mechanism 300 through the cooperation of the needle pitch adjusting seat 241, the fabric feeding eccentric wheel 243 and the connecting rod 244. When it is necessary to adjust the needle pitch, the eccentric position of the fabric feeding eccentric wheel 243 on the main shaft 220 can be changed by changing the state of the locking assembly through the pitch adjusting driving mechanism 400, thereby simplifying the adjustment process and improving the adjustment accuracy.

[0071] In some embodiments, in combination with Figure 2 and Figure 3 The needle pitch adjusting seat 241 comprises a seat body portion and a transmission portion arranged in sequence along the axial direction of the main shaft 220. The seat body portion is fixedly connected with the main shaft 220. The connecting pin 242 is arranged on the side of the transmission portion away from the seat body portion. The connecting pin 242 is the key to eccentric arrangement. The arrangement of the connecting pin 242 allows the fabric feeding eccentric wheel 243 to eccentrically move relative to the main shaft 220 during adjustment.

[0072] The feed eccentric wheel 243 comprises a first main body part 2431 and a first shaft sleeve part 2432 arranged in sequence along the axial direction of the main shaft 220, the outer diameter of the first shaft sleeve part 2432 is smaller than the outer diameter of the first main body part 2431, a second assembly hole is arranged at the edge of the first main body part 2431, the first assembly hole penetrates the first main body part 2431 and the first shaft sleeve part 2432 in sequence, the first end of the connecting rod 244 is sleeved outside the first shaft sleeve part 2432, and the connecting rod 244 abuts against the first main body part 2431.

[0073] By sleeving the first end of the connecting rod 244 outside the first shaft sleeve part 2432, the connecting rod 244 abuts against the first main body part 2431, so that the connecting rod 244 and the feed eccentric wheel 243 form a relatively stable connection, and the position is kept relatively stable when the feed eccentric wheel 243 rotates, the first end of the connecting rod 244 is sleeved outside the first shaft sleeve part 2432 of the feed eccentric wheel 243, when the feed eccentric wheel 243 rotates, the connecting rod 244 also rotates, and the second end is in transmission connection with the feeding mechanism 300, with the rotation and eccentric movement of the feed eccentric wheel 243, the connecting rod 244 drives the feeding mechanism 300 to reciprocate, thereby realizing normal sewing work.

[0074] In some embodiments, in combination Figure 3 A bearing member 260 is further arranged between the first shaft sleeve part 2432 and the connecting rod 244, for example, the bearing member 260 is a ball bearing, and the inner ring and the outer ring of the ball bearing are respectively connected and fixed with the first shaft sleeve part 2432 and the connecting rod 244.

[0075] The bearing member 260 plays a role in reducing friction, and in addition, also has the functions of supporting and bearing load, in the process of driving the connecting rod 244 to swing by the main shaft 220, the bearing member 260 can stably support the connecting rod 244 and the feed eccentric wheel 243, bear the force and moment from all directions, and ensure the stability and reliability of the mechanical structure.

[0076] In some embodiments, in combination Figure 3 The locking assembly comprises a stitch length adjusting cam 250, a locking piece 253 and an outer tooth seat 254.

[0077] The stitch length adjusting cam 250 is sleeved on the main shaft 220 and is arranged eccentrically relative to the main shaft 220, so that when the stitch length adjusting cam 250 rotates, a radial offset relative to the main shaft 220 will be generated, and the offset is the key to realize stitch length adjustment.

[0078] Specifically, the needle spacing adjustment cam 250 includes a second body part 251 and a second shaft sleeve part 252, the second shaft sleeve part 252 is located on the side of the second body part 251 facing the cloth feeding eccentric wheel 243, the second shaft sleeve part 252 is provided in the installation gap, the connecting rod 244 abuts against the second body part 251, in this way, the connecting rod 244 abuts against the first body part 2431 and the second body part 251 respectively, that is, the cloth feeding eccentric wheel 243 and the needle spacing adjustment cam 250 clamp the two sides of the connecting rod 244 respectively, realizing the relative fixation of the connecting rod 244, the cloth feeding eccentric wheel 243 and the needle spacing adjustment cam 250, when the cloth feeding eccentric wheel 243 and the needle spacing adjustment cam 250 are eccentric, the connecting rod 244 is eccentric accordingly, so as to realize the needle spacing adjustment.

[0079] The locking piece 253 has a first position and a second position, and the locking piece 253 is configured to be in a locked state when the eccentric transmission assembly 240 is in the first position, and to be in an unlocked state when the eccentric transmission assembly 240 is in the second position.

[0080] Specifically, the side of the second body part 251 away from the second shaft sleeve part 252 is provided with a sliding rail 2511; the locking piece 253 is movably provided on the sliding rail 2511, the locking piece 253 is provided with a locking rack 2531, and the locking piece 253 is provided with an avoiding hole extending along the length direction of the sliding rail 2511, the main shaft 220 is provided in the avoiding hole, and the avoiding hole is provided to ensure that the locking piece 253 does not interfere with the main shaft 220 when moving.

[0081] The outer tooth seat 254 is sleeved on the main shaft 220 and fixedly connected with the main shaft 220, the outer periphery of the outer tooth seat 254 is provided with a matching tooth 2541, the matching tooth 2541 is engaged with the locking rack 2531 along the extension direction of the sliding rail 2511, the rack is engaged with the matching tooth 2541 on the outer tooth seat 254, and the rack is used for realizing the locking function, the position of the locking piece 253 on the sliding rail 2511 is changed, the engagement state between the matching tooth 2541 and the locking rack 2531 is changed, and then the switching between the locking and the unlocking is realized.

[0082] The distance adjustment driving mechanism 400 is in transmission cooperation with the locking piece 253 to drive the outer tooth seat 254 to move along the sliding rail 2511, so as to switch the eccentric transmission assembly 240 between the locked state and the unlocked state, specifically, in the locked state, the locking rack 2531 is closely engaged with the matching tooth 2541, and the eccentric transmission assembly 240 is prevented from moving radially accidentally; in the unlocked state, the locking rack 2531 is separated from the matching tooth 2541, and the eccentric transmission assembly 240 is allowed to move radially to realize the needle spacing adjustment.

[0083] In some embodiments, in combination with Figure 3 and Figure 5The first main body part 2431 is provided with a slot 2513, the slot 2513 is arranged towards the first push rod 410, the locking piece 253 is located in the slot 2513 when the locking piece 253 is in the initial position, and the first push rod 410 is configured to push the locking piece 253 to slide along the slide rail 2511 when the first push rod 410 is inserted into the slot 2513.

[0084] In the initial state, the locking piece 253 is in the locked state, when the needle pitch needs to be adjusted, the first push rod 410 is inserted into the slot 2513, and as the push rod is inserted, the first push rod 410 pushes the locking piece 253 to slide along the slide rail 2511, thereby achieving the unlocking between the locking piece 253 and the outer tooth seat 254, and then the next adjustment operation is performed.

[0085] In some embodiments, one of the inner wall of the first shaft sleeve part 2432 and the outer wall of the second shaft sleeve part 252 is provided with a limiting key, and the other is provided with a key groove, and the limiting key is engaged in the key groove.

[0086] When the limiting key is engaged in the key groove, a stable axial connection is formed between the first shaft sleeve part 2432 and the second shaft sleeve part 252, and in the needle pitch adjusting device, this design ensures the stability and accuracy of the key components such as the cloth feeding eccentric wheel 243 during rotation and eccentric movement. Through the cooperation of the limiting key and the key groove, it can prevent the inaccuracy or failure of the needle pitch adjustment caused by the loosening or misplacement of the components, and ensure the operation accuracy.

[0087] In some embodiments, in combination with Figure 2 and Figure 3 , the pitch adjusting driving mechanism 400 includes a first push rod 410 and a driving device 420.

[0088] The first push rod 410 is movably arranged along the extension direction of the slide rail 2511, the free end of the first push rod 410 is detachably matched with the locking piece 253 to push the locking piece 253 to move along the slide rail 2511, or is separated from the locking piece 253, and the function of the first push rod 410 is to transmit power to the locking piece 253 to push it to move along the slide rail 2511, thereby changing the meshing state between the locking rack 2531 and the cooperating tooth 2541, and realizing the switching between locking and unlocking.

[0089] The driving device 420 includes a second driving member 421 and a transmission shaft 422, the second driving member 421 is fixedly arranged on the rack 100, the transmission shaft 422 is rotatably supported on the rack 100 and perpendicular to the extension direction of the first push rod 410, the transmission shaft 422 is provided with a first curved member 423, the peripheral wall of the first curved member 423 is provided with a driving protrusion 4231, and when the first curved member 423 rotates with the transmission shaft 422, the driving protrusion 4231 is adapted to push the first push rod 410 to move.

[0090] Optionally, the second driving member 421 and the transmission shaft 422 can be detachably connected, so as to facilitate customization according to different machine types, improve universality, and when the second driving member 421 or the transmission shaft 422 is damaged, the damaged part can be directly replaced without the need for overall replacement, thereby saving maintenance costs.

[0091] When it is necessary to adjust the needle pitch, the second driving member 421 is started, the second driving member 421 drives the transmission shaft 422 to rotate, the rotation of the transmission shaft 422 drives the first curved member 423 to rotate, in the process of rotation, the driving convex part 4231 on the first curved member 423 is in contact with the first push rod 410 and pushes the first push rod 410 to move along the slide rail 2511, so that the switching of the unlocking state is realized through the cooperation of the second driving member 421, the transmission shaft 422 and the first curved member 423.

[0092] At this time, the locking rack 2531 and the matching tooth 2541 cancel the meshing, the eccentric transmission assembly 240 is in the unlocking state, and then the needle pitch adjustment can be performed. Specifically, the first driving member 210 is started to operate at low power to drive the main shaft 220 to rotate at low speed, the main shaft 220 rotates by a preset angle to change the eccentricity of the eccentric transmission assembly 240 from the first eccentricity to the second eccentricity, and because the cloth feeding eccentric wheel 243 is matched with the eccentric transmission assembly 240, the cloth feeding eccentric wheel 243 rotates along the connecting pin 242, the cloth feeding eccentric wheel 243 reaches the preset eccentric position, and the needle pitch adjustment is completed; the second driving member 421 is reversely rotated to reversely move the first push rod 410 through the transmission shaft 422 and the first curved member 423, so that the locking piece 253 is reset, the locking rack 2531 and the matching tooth 2541 are meshed again, the eccentric transmission assembly 240 returns to the locking state, and the accurate control and stable transmission of the needle pitch adjustment are realized.

[0093] In some embodiments, in combination Figure 3 The first elastic reset member 2512 is configured to apply an action force to the locking piece 253 in the direction opposite to the pushing force of the first push rod 410, that is, to push the locking piece 253 to move towards the first position. Exemplarily, the first elastic reset member 2512 can be a torsional spring.

[0094] When the first push rod 410 pushes the locking piece 253 to move along the slide rail 2511 to unlock the eccentric transmission assembly 240, the first elastic reset member 2512 will simultaneously generate a reverse force to try to pull the locking piece 253 back to the original position, and when the pushing force of the first push rod 410 disappears, the first elastic reset member 2512 will automatically reset the locking piece 253, so that the eccentric transmission assembly 240 returns to the locking state.

[0095] In some embodiments, in combination Figure 3 and Figure 4The first push rod 410 is further sleeved with a sealing ring 440. The sealing ring 440 seals between the first push rod 410 and the rack 100, prevents the lubricating oil in the rack from overflowing, and reduces the entry of foreign matters such as dust and lint into the rack 100.

[0096] In some embodiments, in combination with Figure 3 and Figure 4 The distance adjusting driving mechanism 400 further comprises a second elastic reset member 430. The second elastic reset member 430 is sleeved on the first push rod 410. The second elastic reset member 430 is connected with the first push rod 410 and the rack 100 respectively. The second elastic reset member 430 is configured to apply an action force to the first push rod 410 in a direction opposite to the pushing force of the first curved member 423. For example, the second elastic reset member 430 can be a spring or an elastic tube.

[0097] When the driving device 420 works, the first curved member 423 pushes the first push rod 410 to move through the driving convex part 4231. At this time, the second elastic reset member 430 generates a reverse force to try to push the first push rod 410 back to the original position. When the driving device 420 stops working, the first push rod 410 can be automatically reset by the action of the second elastic reset member 430, thereby improving the stability of the system.

[0098] In some embodiments, in combination with Figure 4 The distance adjusting driving mechanism 400 can further comprise a second push rod and a third elastic reset member. The second push rod is movably arranged on the rack 100 along the extension direction of the slide rail 2511. The free end of the second push rod is detachably matched with the locking piece 253. The second push rod is oppositely arranged with the first push rod 410. The third elastic reset member is sleeved on the second push rod. The third elastic reset member is connected with the second push rod and the rack 100 respectively. For example, the third elastic reset member can be a spring or an elastic tube.

[0099] The second push rod is a manual push rod. The third elastic reset member is used to automatically reset the second push rod to the initial position by the elastic force of the third elastic reset member when the second push rod is released after the operator manually pushes the second push rod. When the first push rod 410 cannot normally operate due to some reasons such as power failure or mechanical failure, it is necessary to switch to the manual operation mode. At this time, the user can still adjust the operation by operating the second push rod.

[0100] In some embodiments, in combination with Figure 3 The feeding mechanism 300 comprises a tooth frame 310, a feeding tooth 320 and a second curved member 330.

[0101] The tooth frame 310 is movably arranged on the lifting tooth shaft sleeve 230 along the radial direction of the main shaft 220, and has a first assembly end 311 and a second assembly end 312 opposite to each other along the moving direction of the tooth frame 310; the feed dog 320 is arranged on the first assembly end 311; the second bending member 330 is rotatably arranged on the second assembly end 312, and the second end of the connecting rod 244 is connected with the second bending member 330 and drives the second bending member 330 to move synchronously. During the sewing process, the feed dog 320 moves forward and backward through the swing of the tooth frame 310, and the fabric is sent into the sewing area at a preset speed and direction.

[0102] During the sewing operation, the main shaft 220 drives the connecting rod 244 to swing, the connecting rod 244 drives the second bending member 330 to rotate, and the rotation of the second bending member 330 is transmitted through the tooth frame 310, so that the feed dog 320 moves forward and backward correspondingly, and the fabric is sent into the sewing area at a preset speed and direction, thereby realizing the sewing operation.

[0103] In some embodiments, in combination with Figure 2 and Figure 3 , the second end of the connecting rod 244 is provided with a first pin hole, and the second bending member 330 is provided with a second pin hole; the feeding mechanism 300 further comprises a differential bending member 340, the differential bending member 340 is provided with a third pin hole and a fourth pin hole, the first pin hole and the third pin hole are connected through a first pin shaft 350, and the second pin hole and the fourth pin hole are connected through a second pin shaft 360.

[0104] During the feeding process of the sewing machine, the main shaft 220 drives the connecting rod 244 to swing, the movement of the connecting rod 244 is transmitted to the differential bending member 340 through the cooperation of the first pin shaft 350 and the first pin hole and the third pin hole, the differential bending member 340 transmits the movement to the second bending member 330 through the cooperation of the second pin shaft 360 and the fourth pin hole and the second pin hole, the second bending member 330 drives the tooth frame 310 to swing, and then the tooth frame 310 and the feed dog 320 move according to the preset trajectory and speed, and the feeding operation of the fabric is realized.

[0105] In some embodiments, in combination with Figure 1 and Figure 3 , the rack 100 is further provided with an electric control system 500, and the electric control system 500 is connected with the first driving member 210 and the second driving member 421, specifically, the electric control system 500 is responsible for receiving and processing instruction signals, and transmits control signals to at least one of the first driving member 210 and the second driving member 421 through wires, so as to control at least one of the main shaft 220 and the transmission shaft 422 to rotate.

[0106] In some embodiments, in combination with Figure 1 and Figure 3The rack 100 is further provided with a transmitting sensor 600 and a receiving sensor 700, which are symmetrically arranged around the sewing area, wherein the receiving sensor 700 is provided with at least two, and the receiving sensors 700 are sequentially arranged along the running direction of the feed dog 320.

[0107] Specifically, the transmitting sensor 600 is used to transmit signals to the sewing area, and the receiving sensor 700 is used to receive signals and feedback to the electric control system 500, so as to monitor the state of the sewing area, avoid unqualified sewing caused by insufficient cloth supply or cloth not pushed into place, or detect the running of the feed dog 320 and the movement of the cloth, so as to ensure that the cloth maintains a preset position and speed during sewing. When the movement speed of the cloth, i.e. the feeding speed of the feed dog 320, does not match the preset value, the receiving sensor 700 feeds back to the electric control system 500, and the electric control system 500 drives the operation of the main drive mechanism 200 and the driving device 420 according to the preset program to adjust the feeding speed of the feed dog 320, so as to realize the adjustment of the running speed and the stitch length of the cloth.

[0108] On the other hand, the present application also provides a sewing machine comprising the stitch length adjustment device of the sewing machine in any of the above embodiments.

[0109] By setting the stitch length adjustment device of the sewing machine, the distance adjustment drive mechanism 400 realizes automatic adjustment of the stitch length, avoids the tediousness and errors of manual operation, and in addition, the design of the locking assembly and the eccentric transmission assembly 240 ensures the accuracy of the stitch length adjustment, reduces the number of repeated adjustments, improves the operation efficiency, and ensures the efficient operation of the sewing machine.

[0110] The embodiments or implementations in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts between the embodiments can be referred to each other.

[0111] It should be noted that the embodiments referred to in the specification as "one embodiment", "embodiment", "exemplary embodiment", "some embodiments" and the like can include specific features, structures or characteristics, but not necessarily every embodiment includes the specific features, structures or characteristics. In addition, such phrases do not necessarily refer to the same embodiment. In addition, when a specific feature, structure or characteristic is described in combination with an embodiment, it is within the knowledge of those skilled in the art to realize such feature, structure or characteristic in combination with other embodiments that are explicitly or implicitly described.

[0112] In general, terminology can be understood at least in part from an ordinary sense of the corresponding terminology as would be understood by those of ordinary skill in the art to which the subject matter concerns when context permits. For example, terms such as "or" as used herein can be understood, at least in part, to be an inclusive, meaning and / or. Similarly, terms such as "one or more" as used herein can be understood, at least in part, to convey a meaning of one or more than one, depending on the context.

[0113] It should be readily understood that the terms "on," "above," and "over" in the present disclosure are to be interpreted in the broadest context possible so that "on" means not only "directly on something" but also includes the meaning of "on something" with intervening features or layers therebetween, and "above" or "over" includes not only the meaning of "above" or "over something" but also can include the meaning of "above" or "over something" with no intervening features or layers therebetween (i.e., directly on something).

[0114] Finally, it should be noted that the above-described embodiments are merely intended to illustrate the technical solutions of the present application, but not to limit the same; even though the present application has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that they can still make modifications to the technical solutions recorded in the above embodiments, or make equivalent replacements to some or all of the technical features thereof; and such modifications or replacements do not cause the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A stitch length adjustment device for a sewing machine, characterized in that, include: Rack (100); A main drive mechanism (200) is disposed on the frame (100). The main drive mechanism (200) includes an eccentric transmission assembly (240) and a locking assembly. The eccentric transmission assembly (240) is rotatable relative to the frame (100). The locking assembly and the eccentric transmission assembly (240) switch between a locked state and an unlocked state. In the locked state, the eccentric transmission assembly (240) has a first eccentricity. In the unlocked state, the eccentric transmission assembly (240) has a second eccentricity. An adjustable distance drive mechanism (400) is provided on the frame (100) and is in drive cooperation with the locking assembly to drive the eccentric drive assembly (240) to switch between the locked state and the unlocked state; The feeding mechanism (300) is movably disposed on the frame (100) and is connected to the eccentric transmission assembly (240) in a transmission manner; The eccentric transmission assembly (240) includes: A needle pitch adjustment seat (241) is sleeved on the main shaft (220) and fixedly connected to the main shaft (220). A connecting pin (242) is provided on the side of the needle pitch adjustment seat (241) facing away from the tooth lifting bushing (230). The connecting pin (242) is eccentrically set with the main shaft (220). The feeding eccentric wheel (243) is provided with a first mounting hole and a second mounting hole. The first mounting hole is eccentrically set, and the inner diameter of the first mounting hole is larger than the outer diameter of the main shaft (220). The main shaft (220) passes through the first mounting hole and defines an assembly gap between itself and the inner wall of the first mounting hole. The connecting pin (242) passes through the second mounting hole. The connecting rod (244) has its first end connected to the feeding eccentric wheel (243) and its second end connected to the feeding mechanism (300) for transmission.

2. The stitch length adjustment device for a sewing machine according to claim 1, characterized in that, The locking assembly includes a locking plate (253) having a first position and a second position. The locking plate (253) is configured such that, in the first position, the eccentric drive assembly (240) is in the locked state, and in the second position, the eccentric drive assembly (240) is in the unlocked state. The adjustable drive mechanism (400) engages with the locking plate (253) to switch the eccentric drive assembly (240) between the locked state and the unlocked state.

3. The stitch length adjustment device for a sewing machine according to claim 2, characterized in that, The pitch adjustment drive mechanism (400) includes: The first push rod (410) is movably disposed on the frame (100) along the sliding direction of the locking piece (253). The free end of the first push rod (410) is detachably engaged with the locking piece (253) to push the locking piece (253) to move along a preset trajectory or to separate from the locking piece (253). The drive device (420) includes a second drive member (421) and a transmission shaft (422). The second drive member (421) is fixedly mounted on the frame (100). The transmission shaft (422) is rotatably supported on the frame (100) and is perpendicular to the extension direction of the first push rod (410). The transmission shaft (422) is provided with a first crank member (423). The peripheral wall of the first crank member (423) is provided with a drive protrusion (4231). When the first crank member (423) rotates with the transmission shaft (422), the drive protrusion (4231) is adapted to push the first push rod (410) to move.

4. The stitch length adjustment device for a sewing machine according to claim 3, characterized in that, The locking plate (253) is also connected to a first elastic reset member (2512), which is configured to apply a force to the locking plate (253) in the opposite direction to the thrust of the first push rod (410), i.e., to push the locking plate (253) toward the first position; and / or, The pitch adjustment drive mechanism (400) further includes a second elastic reset member (430), which is sleeved on the first push rod (410). The second elastic reset member (430) is connected to the first push rod (410) and the frame (100) respectively. The second elastic reset member (430) is configured to apply a force to the first push rod (410) in the opposite direction to the thrust of the first crank member (423).

5. The stitch length adjustment device for a sewing machine according to claim 2, characterized in that, The main drive mechanism (200) further includes a first drive member (210), a main shaft (220), and a tooth lifting bushing (230). One end of the main shaft (220) is connected to the first drive member (210), and the other end passes through the tooth lifting bushing (230) and is rotatable relative to the tooth lifting bushing (230). The eccentric transmission assembly (240) is located on the part of the main shaft (220) that passes through the tooth lifting bushing (230).

6. The stitch length adjustment device for a sewing machine according to claim 5, characterized in that, The needle pitch adjustment seat (241) includes a seat body and a transmission part arranged sequentially along the axial direction of the main shaft (220). The seat body is fixedly connected to the main shaft (220), and the connecting pin (242) is located on the side of the transmission part opposite to the seat body. The feeding eccentric wheel (243) includes a first main body (2431) and a first bushing (2432) arranged sequentially along the axial direction of the main shaft (220). The outer diameter of the first bushing (2432) is smaller than the outer diameter of the first main body (2431). The second mounting hole is provided at the edge of the first main body (2431). The first mounting hole passes through the first main body (2431) and the first bushing (2432) in sequence. The first end of the connecting rod (244) is sleeved on the outside of the first bushing (2432). The connecting rod (244) abuts against the first main body (2431).

7. The stitch length adjustment device for a sewing machine according to claim 6, characterized in that, The locking component further includes: A stitch pitch adjusting cam (250) is sleeved on the main shaft (220) and eccentrically disposed relative to the main shaft (220). The stitch pitch adjusting cam (250) includes a second main body (251) and a second bushing (252). The second bushing (252) is located on the side of the second main body (251) facing the feed eccentric wheel (243). The second bushing (252) passes through the installation gap. The connecting rod (244) abuts against the second main body (251). A slide rail (2511) is provided on the side of the second main body (251) facing away from the second bushing (252). The locking plate (253) is movably disposed on the slide rail (2511), the locking plate (253) is provided with a locking rack (2531), the locking plate (253) is provided with a clearance hole extending along the length direction of the slide rail (2511), and the main shaft (220) passes through the clearance hole; An external gear seat (254) is sleeved on the main shaft (220) and fixedly connected to the main shaft (220). The outer periphery of the external gear seat (254) is provided with mating teeth (2541). The mating teeth (2541) mesh with the locking rack (2531) along the extension direction of the slide rail (2511). The pitch adjustment drive mechanism (400) is in transmission cooperation with the locking plate (253) to drive the external gear seat (254) to move along the slide rail (2511).

8. The stitch length adjustment device for a sewing machine according to claim 7, characterized in that, One of the inner wall of the first bushing part (2432) and the outer wall of the second bushing part (252) is provided with a limiting key, and the other is provided with a keyway. The limiting key is engaged in the keyway.

9. The stitch length adjustment device for a sewing machine according to claim 5, characterized in that, The feeding mechanism (300) includes: The tooth frame (310) is movably disposed on the tooth lifting bushing (230) along the radial direction of the main shaft (220), and the tooth frame (310) has a first mounting end (311) and a second mounting end (312) opposite to each other in its own moving direction. A feed dog (320) is provided at the first assembly end (311). The second crank component (330) is rotatably disposed on the second assembly end (312). The second end of the connecting rod (244) is connected to the second crank component (330) and drives the second crank component (330) to move synchronously.

10. A sewing machine, characterized in that, include: The stitch length adjustment device for the sewing machine according to any one of claims 1-9.

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