Feed dog assembly, thread trimming mechanism and presser foot lifting mechanism for a sewing machine

Abstract

The application provides a feed dog assembly and thread cutting and presser foot lifting mechanism of a sewing machine, and particularly relates to the technical field of sewing machine manufacturing, and has a power source one and a power source two, characterized in that the feed dog assembly is driven by the power source one and the power source two, and the power source one and the power source two jointly act on a feed dog frame of the feed dog assembly to perform a feed action of the sewing machine. A brand-new feed dog assembly structure is provided, meanwhile, a thread cutting action and a presser foot lifting action are performed by the single power source one, and are continuously performed after the power source one and the power source two jointly perform the feed action. The utilization rate of a power device of the sewing machine is improved, and the intelligent control level of a power system of the sewing machine is further improved, the power sources required by the thread cutting action and the presser foot lifting action are saved, and the sewing machine has high popularization and application value.

Description

TECHNICAL FIELD

[0001] The application provides a feed dog assembly, thread trimming mechanism and presser foot lifting mechanism of a sewing machine, and particularly relates to the technical field of sewing machine manufacturing. BACKGROUND

[0002] The feed dog is one of the essential parts of the sewing machine to realize the sewing work. The applicant previously proposed a feed dog assembly of a split type sewing machine, and the specific scheme is that the upper and lower lifting motor and the front and rear feed motor of the feed dog assembly apply a non-lateral swing source to the feed dog, the upper and lower lifting motor and the front and rear feed motor indirectly act on the feed dog to execute the feed action, the front and rear feed motor drives the rotating disc to drive the connecting rod, the connecting rod is movably connected to the eccentric position of the rotating disc, and the connecting rod movably connects the feed dog connecting frame. The upper and lower lifting motor and the front and rear feed motor transmit the swing source to the feed dog assembly, the feed dog assembly can be installed on the bottom thread mechanism and manufactured into a modularized product to be used on various sewing machines. In the above-mentioned sewing machine, the thread trimming and presser foot lifting devices need to be installed, and the power for driving the above-mentioned thread trimming and presser foot lifting actions needs to be installed, so that the manufacturing cost of the sewing machine is increased. SUMMARY

[0003] In view of the problem of increased manufacturing cost of the above-mentioned sewing machine, the application particularly provides a feed dog assembly of a sewing machine, which has a power source one and a power source two, and is characterized in that the feed dog assembly is driven by the power source one and the power source two, and the power source one and the power source two jointly act on the feed dog frame of the feed dog assembly to execute the feed action of the sewing machine.

[0004] Preferably, the output shaft of the power source two is provided with a crank, the output shaft of the power source one is provided with a synchronous pulley, the crank indirectly acts on the feed dog frame to realize the front and rear feed action of the feed dog assembly, and the synchronous pulley indirectly acts on the multi-stage cam one and the multi-stage cam two to realize the up and down lifting feed action of the feed dog assembly.

[0005] Preferably, the crank installed on the output shaft is hinged to a swing rod, the crank drives the swing rod to operate, the swing rod is hinged to the feed dog frame, the feed dog frame is provided with a supporting shaft, the supporting shaft is clearance fitted on the feed dog frame, the supporting shaft extends out of the feed dog frame and extends to both ends of the support, and the feed dog frame operates in the support.

[0006] Preferably, the front output shaft of the power source one is provided with a synchronous pulley, the synchronous pulley drives the synchronous pulley two and the synchronous pulley three through a synchronous belt to connect the multi-stage cam one and the multi-stage cam two, the multi-stage cam one and the multi-stage cam two are respectively located at both ends of the bottom of the support, and the multi-stage cam one and the multi-stage cam two have a convex point one and a convex point two.

[0007] Preferably, the multi-stage cam one is fixed on the rotating shaft one and the multi-stage cam two is fixed on the rotating shaft two, and the rotating shaft one and the rotating shaft two are sleeved on the feed dog fixed support.

[0008] Preferably, the gear two is additionally installed behind the gear four of the rotating shaft one or the gear three of the rotating shaft two, the additionally installed gear two is engaged with the gear one, the gear one drives the gear two and drives the gear four and the gear three in parallel.

[0009] Preferably, the feed dog fixed support further has the limiting support one and the limiting support two which can fix the power source one and the power source two, the feed dog fixed support further has the limiting block one and the limiting block two which are used to limit the running position of the feed dog frame and / or support, and the feed dog assembly further has the swing range rod and the swing hole of the feed dog fixed support.

[0010] Preferably, the gear one is installed on the front output shaft of the power source one, the multi-stage cam one is installed on the rotating shaft one, the multi-stage cam two is installed on the rotating shaft two, the rotating shaft one and the rotating shaft two pass through the feed dog fixed support, the gear four and the gear three are installed on the rotating shaft one and the rotating shaft two of the feed dog fixed support, and the gear four and the gear three are engaged.

[0011] The application also claims a thread cutting mechanism and a presser foot lifting mechanism of a sewing machine, which has the power source one, the thread cutting crank is installed on the front output shaft of the power source one, the thread cutting crank acts on the thread cutting fork rod, the thread cutting fork rod has the thread cutting rod and the return rod, the thread cutting crank has the shaft sleeve, the shaft sleeve is located between the thread cutting rod and the return rod, and the thread cutting end is finally acted on by the thread cutting fork rod to realize the thread cutting action.

[0012] Preferably, the shaft sleeve pushes the thread cutting rod to execute the thread cutting, the shaft sleeve pushes the return rod to execute the thread cutting return, and the thread cutting rod and the return rod can be interchanged in the up and down positions of the thread cutting fork rod.

[0013] Preferably, the presser foot lifting cam is installed on the rear output shaft of the power source one, the cam part of the presser foot lifting cam driven by the power source one acts on the presser foot lifting top rod, and the presser foot lifting end is finally acted on by the presser foot lifting top rod to execute the presser foot lifting action.

[0014] Compared with the prior art, the feed dog assembly of the present application is driven by the power source one and the power source two together, fully embodies the feed dog assembly to perform the feeding function of the sewing machine, and provides a brand-new feed dog assembly structure. At the same time, only the power source one is used to perform the thread cutting action of the thread cutting mechanism and the presser foot lifting action of the presser foot lifting mechanism, realizes that the thread cutting action and the presser foot lifting action are performed by the single power source one, and are continuously performed after the power source one and the power source two jointly perform the feeding action, not only improves the utilization rate of the power device of the sewing machine, but also further improves the intelligent control level of the power system of the sewing machine, saves the power source required for the thread cutting action and the presser foot lifting action, greatly reduces the manufacturing cost of the sewing machine, and has high popularization and use value. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a global view of the feed dog assembly, thread cutting mechanism and presser foot lifting mechanism of the sewing machine of the present application;

[0016] Figure 2 is a front view of the feed dog assembly of the feed dog assembly, thread cutting mechanism and presser foot lifting mechanism of the sewing machine of the present application;

[0017] Figure 3 is a structure diagram of the feed dog assembly of the feed dog assembly, thread cutting mechanism and presser foot lifting mechanism of the sewing machine of the present application;

[0018] Figure 4 is an exploded view of the feed dog assembly of the feed dog assembly, thread cutting mechanism and presser foot lifting mechanism of the sewing machine of the present application;

[0019] Figure 5 is a position diagram of the feed dog swing rod of the feed dog assembly, thread cutting mechanism and presser foot lifting mechanism of the sewing machine of the present application;

[0020] Figure 6 is a bracket structure diagram of the feed dog assembly, thread cutting mechanism and presser foot lifting mechanism of the sewing machine of the present application;

[0021] Figure 7 is a gear scheme diagram of the second embodiment of the feed dog assembly, thread cutting mechanism and presser foot lifting mechanism of the sewing machine of the present application.

[0022] Reference numerals: 10 feed dog assembly, 11 feed dog holder, 12 multi-stage cam one, 121 rotating shaft one, 13 multi-stage cam two, 131 rotating shaft two, 14 swing rod, 15 support shaft, 16 bracket, 161 protrusion one, 162 protrusion two, 163 swing hole, 164 limit block one, 165 limit block two, 166 limit bracket one, 167 limit bracket two, 18 swing rod, 20a thread cutting mechanism, 20b presser foot lifting mechanism, 20b presser foot lifting mechanism. Cam 21, presser foot lifting rod 22, wire cutting crank 23, bushing 231, wire cutting fork rod 24, wire cutting rod 241, return rod 242, wire cutting end actuator 25, power source one 30, front output shaft 31, rear output shaft 32, power source two 40, output shaft 41, crank 42, synchronous pulley 51, synchronous pulley two 52, synchronous pulley three 53, feed dog fixing bracket 6, gear one 71, gear two 72, gear three 73, gear four 74. Detailed Implementation

[0023] The following is in conjunction with the appendix Figures 1-7 The preferred embodiments of this application are described in detail so that the advantages and features of this application can be more easily understood by those skilled in the art, thereby making a clearer and more explicit definition of the scope of protection of this application. These embodiments are only used to illustrate the present invention and are not intended to limit the present invention.

[0024] Example 1

[0025] exist Figures 1-6 This application discloses a feed dog assembly, a thread cutting mechanism, and a presser foot lifting mechanism for a sewing machine, comprising a feed dog assembly 10, a thread cutting mechanism 20a, a presser foot lifting mechanism 20b, a power source 30, and a power source 40. The feed dog assembly 10 is jointly driven by the power source 30 and the power source 40, which together act on the feed dog assembly 10 to perform the feed action of the sewing machine, enabling the feed dog assembly 10 to fulfill the essential feed function of the sewing machine. After the feed action of the feed dog assembly 10 is completed, the power source 30 starts to drive the thread cutting mechanism 20a and the presser foot lifting mechanism 20b to perform the thread cutting and presser foot lifting actions. First, the front output shaft 31 installed on the power source 30 performs the thread cutting action of the thread cutting mechanism 20a; then, the rear output shaft 32 installed on the power source 30 performs the presser foot lifting action of the presser foot lifting mechanism 20b. This application utilizes the power source 40 of the feed dog assembly 10 to perform the presser foot lifting and thread cutting actions after the feed action is completed, thereby improving the power utilization rate of the sewing machine, eliminating the power required to perform the presser foot lifting and thread cutting actions, and significantly reducing the manufacturing cost of the sewing machine.

[0026] The output shaft 41 of the power source two 40 is provided with a crank 42; the output shaft 41 of the power source one 30 is provided with a synchronous pulley 51, the crank 42 indirectly acts on the feed dog holder 11 to realize the forward and backward feeding action of the feed dog assembly 10, the synchronous pulley 51 indirectly acts on the multi-stage cam one 12 and the multi-stage cam two 13 to realize the up and down lifting feeding action of the feed dog assembly 10, the forward and backward feeding action and the up and down lifting feeding action are performed simultaneously to realize the feeding action of the sewing machine.

[0027] In the feeding action angle area of the power source two 40, the crank 42 installed on the output shaft 41 is hinged to the swing rod 18, the crank 42 drives the swing rod 18 to operate, the swing rod 18 is hinged to the feed dog holder 11 to make the output shaft 41 generate the forward and backward movement swing source to the feed dog holder 11. The support shaft 15 is arranged on the feed dog holder 11, the support shaft 15 is clearance fitted on the feed dog holder 11, the support shaft 15 extends out of the feed dog holder 11 and extends to both ends of the bracket 16, the feed dog holder 11 operates in the bracket 16. The power source two 40 drives the crank 42 to make the swing rod 18 generate the forward and backward movement swing source to the feed dog holder 11.

[0028] The forward output shaft 31 of the power source one 30 is provided with a synchronous pulley 51, the synchronous pulley 51 drives the synchronous pulley two 52 and the synchronous pulley three 53 through the synchronous belt to be connected to the multi-stage cam one 12 and the multi-stage cam two 13 to realize the up and down lifting feeding action of the entire feed dog assembly 10, the multi-stage cam one 12 and the multi-stage cam two 13 are respectively arranged at both ends of the bottom of the bracket 16. The power source one 30 drives the synchronous pulley two 52 and the synchronous pulley three 53 in the power source feeding action angle area, specifically, the multi-stage cam one 12 is fixed on the rotating shaft one 121 and the multi-stage cam two 13 is fixed on the rotating shaft two 131, the rotating shaft one 121 and the rotating shaft two 131 are sleeved on the feed dog fixed bracket 6. The multi-stage cam one 12 and the multi-stage cam two 13 have a convex point one 161 and a convex point two 162, the convex point one 161 and the convex point two 162 are arranged to generate the up and down lifting swing source of the bracket 16 and the entire feed dog assembly 10 under the driving of the power source one 30.

[0029] The feed dog assembly 10 of the present application is fixed on the feed dog fixing support 6, and the feed dog assembly 10 further has a swing rod 14 which is in a cylindrical shape. The feed dog fixing support 6 has a swing hole 163 which provides a space for the swing rod 14 to move up and down, and the swing of the swing source of the multi-stage cam 1 and the multi-stage cam 2 is limited by the swing hole 163 of the feed dog fixing support 6. In addition, the feed dog fixing support 6 further has a limiting support 1 166 and a limiting support 2 167 which can fix the power source 1 30 and the power source 2 40, and the limiting support 1 166, the limiting support 2 167 and the body of the feed dog fixing support 6 form an integral whole. The feed dog fixing support 6 further has a limiting block 1 164 and a limiting block 2 165 which are used to limit the running position of the feed dog support 11 and / or the support 16, so that the feed dog assembly 10 has a fixed running structure.

[0030] After the above-mentioned feed motion of the sewing machine is completed, the power source 1 30 starts to perform the thread trimming motion and the presser foot lifting motion. The front output shaft 31 of the power source 1 30 is provided with a thread trimming crank 23, the thread trimming crank 23 acts on a thread trimming fork rod 24, and the thread trimming fork rod 24 acts on a thread trimming end execution part 25 to realize the thread trimming motion. The thread trimming fork rod 24 has a thread trimming rod 241 and a return rod 242, and the thread trimming crank 23 has a shaft sleeve 231 which is located between the thread trimming rod 241 and the return rod 242, the shaft sleeve 231 pushes the thread trimming rod 241 to perform thread trimming, and the shaft sleeve 231 pushes the return rod 242 to perform thread trimming return. The above-mentioned thread trimming rod 241 and the return rod 242 can be interchanged in the up and down positions of the thread trimming fork rod 24, and the technical effects realized by them are the same.

[0031] The rear output shaft 32 of the above-mentioned power source 1 30 is provided with a presser foot lifting cam 21, and under the drive of the power source 1 30, the cam part of the presser foot lifting cam 21 acts on a presser foot lifting top rod 22, and the presser foot lifting top rod 22 acts on a presser foot lifting end execution part to realize the presser foot lifting motion.

[0032] The running angle of the above-mentioned feed motion, presser foot lifting motion and thread trimming motion of the power source 2 40 is respectively a feed motion angle area, a presser foot lifting motion angle area and a thread trimming motion angle area. The sequence of the sewing motions performed by the power source 2 40 is feed motion, thread trimming motion and presser foot lifting motion. It is worth mentioning that after the completion of the feed motion of the sewing machine, the power source 2 40 is shifted to the running angle to perform the thread trimming motion and the presser foot lifting motion, in other words, the feed motion, the presser foot lifting motion and the thread trimming motion do not overlap in the running angle area of the power source 2 40, and after the machine is stopped, the thread trimming is performed first and then the presser foot lifting is performed.

[0033] In the corner area of the feed motion, the crank 42 is hinged to the swing lever 18 to generate the front and back feed swing source to the feed dog holder 11. When the sewing is finished, the power source 2 40 leaves the corner area of the feed motion and enters the corner area of the presser foot lifting motion and the corner area of the thread cutting motion. Since the power source 1 30 contacts the idle circular arc surface of the multi-stage cam 1 12 and the multi-stage cam 2 13 below the support 16 when it is driving the corner area of the presser foot lifting motion and the corner area of the thread cutting motion, the power source 1 30 does not generate the up and down lifting motion to the support 16, and at the same time, the power source 2 40 is in the stop state, thus the whole feed dog assembly 10 is stationary. Similarly, when the power source 2 40 is driving in the corner area of the feed motion, the shaft sleeve 231 of the thread cutting crank 23 idles back and forth between the thread cutting lever 24 between the thread cutting rod 241 and the return rod 242; the circular arc surface of the presser foot cam 21 also idles back and forth to the presser foot lifting rod 22, thus the feed motion, the presser foot lifting motion and the thread cutting motion performed by the power source 2 40 do not affect each other, and the motions are clear and distinct.

[0034] Embodiment 2

[0035] The embodiment 2 is basically the same as the above-mentioned embodiment 1, and the difference is that the implementation technical means of the swing source generated by the power source 1 30 to the feed dog assembly 10 is different. In the attached Figure 7 , the power source 1 30 also realizes the above-mentioned sewing motion of the feed dog assembly 10 in the form of gear transmission. The front output shaft 31 of the power source 1 30 is provided with a gear 1 71, the multi-stage cam 1 12 is installed on the rotating shaft 1 121, and the multi-stage cam 2 13 is installed on the rotating shaft 2 131. The rotating shaft 1 121 and the rotating shaft 2 131 pass through the feed dog fixed support 6, and the rotating shaft 1 121 and the rotating shaft 2 131 passing through the feed dog fixed support 6 are provided with a gear 4 74 and a gear 3 73, and the gear 4 74 and the gear 3 73 are engaged. In this embodiment, the gear 4 74 of the rotating shaft 1 121 or the gear 3 73 of the rotating shaft 2 131 is additionally provided with a gear 2 72, and the additionally provided gear 2 72 is engaged with the gear 1 71, and the gear 1 71 drives the gear 2 72 and drives the gear 4 74 and the gear 3 73.

[0036] Alternatively, the gear 1 71 is directly engaged with the gear 2 72, and the gear 2 72 is omitted, and the above-mentioned technical effect can also be realized. Under the driving of the power source 1 30, the front output shaft 31 is provided with the gear 1 71, which drives the rotating shaft 1 121 or the rotating shaft 2 131 through the additionally provided gear 2 72, and the technical effect of the swing source generated by the feed dog assembly 10 is the same.

[0037] The above-mentioned is only the preferred embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent flow transformation using the content of the specification and the attached drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A feed dog assembly for a sewing machine having a first power source (30) and a second power source (40), characterized in that The feeding tooth assembly (10) is driven by a power source one (30) and a power source two (40), and the power source one (30) and the power source two (40) jointly act on the feeding tooth frame (11) of the feeding tooth assembly (10) to perform the feeding action of the sewing machine. The output shaft (41) of the power source two (40) is provided with a crank (42); the crank (42) is hinged to the swing rod (18), and the crank (42) drives the swing rod (18) to operate; the swing rod (18) is hinged to the feeding tooth frame (11); the feeding tooth frame (11) is provided with a support shaft (15); the support shaft (15) is clearance-fitted on the feeding tooth frame (11); the support shaft (15) extends out of the feeding tooth frame (11) and extends to both ends of the support frame (16); and the feeding tooth frame (11) operates in the support frame (16). The front output shaft (31) of the power source one (30) is provided with a synchronous pulley (51); the synchronous pulley (51) drives the synchronous pulley two (52) and the synchronous pulley three (53) through a synchronous belt to connect the multi-stage cam one (12) and the multi-stage cam two (13); the multi-stage cam one (12) and the multi-stage cam two (13) are respectively located at both ends of the bottom of the support frame (16); the multi-stage cam one (12) and the multi-stage cam two (13) are provided with a convex point one (161) and a convex point two (162); and the convex point one (161) and the convex point two (162) are driven by the power source one (30) to make the support frame (16) and the feeding tooth assembly (10) as a whole produce up-and-down swinging movement; the synchronous pulley (51) indirectly acts on the multi-stage cam one (12) and the multi-stage cam two (13) to realize the up-and-down feeding movement of the feeding tooth assembly (10); the multi-stage cam one (12) is fixed on a rotating shaft one (121); the multi-stage cam two (13) is fixed on a rotating shaft two (131); and the rotating shaft one (121) and the rotating shaft two (131) are sleeved on the feeding tooth fixed support (6).

2. The feed dog assembly of claim 1 wherein, The gear four (74) of the rotating shaft one (121) or the gear three (73) of the rotating shaft two (131) is additionally provided with a gear two (72) at the rear; the additionally provided gear two (72) is engaged with a gear one (71); and the gear one (71) drives the gear two (72) and drives the gear four (74) and the gear three (73) in linkage.

3. The feed dog assembly of claim 1 wherein, The feeding tooth fixed support (6) is further provided with a limiting support one (166) and a limiting support two (167) for limiting the power source one (30) and the power source two (40), and a limiting block one (164) and a limiting block two (165); the limiting block one (164) and the limiting block two (165) are used to limit the running positions of the feeding tooth frame (11) and the support frame (16); the feeding tooth assembly (10) is further provided with a swing rod (14); the feeding tooth fixed support (6) is provided with a swing hole (163); and the swing hole (163) provides a space for the swing rod (14) to move up and down.

4. The feed dog assembly of claim 1 wherein The front output shaft (31) of the power source one (30) is installed with gear one (71), the rotating shaft one (121) and rotating shaft two (131) pass through the fixed support (6) of the feed dog, the rotating shaft one (121) and rotating shaft two (131) of the fixed support (6) of the feed dog are installed with gear four (74) and gear three (73), and the gear four (74) and gear three (73) are engaged.

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