Conjugate cam presser foot driving device and embroidery machine

Abstract

The utility model discloses a conjugate cam presser foot driving device and an embroidery machine, and relates to the embroidery technology, the conjugate cam presser foot driving device comprises a conjugate connecting rod assembly driven by a conjugate cam, and the conjugate cam is provided with an inner cam surface and an outer cam surface; the conjugate connecting rod assembly comprises a conjugate connecting rod rotationally connected to the first conjugate connecting rod pin and a presser foot driving connecting rod rotationally connected to the second conjugate connecting rod pin, the conjugate connecting rod is provided with a first transmission part and a second transmission part, and the presser foot driving connecting rod is provided with a presser foot driving part; the first transmission part is matched with the inner cam surface, and the second transmission part is matched with the outer cam surface, so that the conjugate cam drives the conjugate connecting rod to rotate through the first transmission part and the second transmission part, the conjugate connecting rod drives the presser foot driving connecting rod to rotate, the presser foot driving part is arranged below the presser foot positioning block, and the presser foot positioning block is connected with the presser foot. And the presser foot driving connecting rod is synchronous with the lifting of the presser foot when driving the presser foot to work, so that the presser foot driving part is always in contact with the bottom surface of the presser foot positioning block.

Description

[Technical Field]

[0001] This utility model belongs to the technical field of embroidery equipment, specifically relating to embroidery machines. [Background Technology]

[0002] In the field of embroidery machine technology, the presser foot is driven in two ways: one is combined with the needle bar movement, where the needle bar drives the presser foot to reciprocate up and down; the other is an independent presser foot, driven by an independent power source to reciprocate up and down, with the independent presser foot and the needle bar's reciprocating up and down movements not interfering with each other. Currently, the application of independent presser feet is becoming increasingly common.

[0003] Referring to Chinese invention patent application CN117802706 A, a differential speed coordination device for a presser foot is disclosed, including a main shaft, a first cam and a second cam disposed on the main shaft, a needle bar, a presser foot slidably sleeved on the needle bar, a first transmission member having a first rotation fulcrum, and a presser foot drive block that can be raised and lowered and moved; the transmission member and the presser foot drive block are directly or indirectly movably connected; the transmission member has a first roller and a second roller; the rolling engagement between the outer cam surface of the first roller and the first cam causes the presser foot drive block to cooperate with the rising stroke of the presser foot, and the rolling engagement between the outer cam surfaces of the second roller and the second cam causes the presser foot drive block to cooperate with the falling stroke of the presser foot. Because both the first cam and the second cam need to be simultaneously disposed on the main shaft to complete the independent rising and falling strokes of the presser foot, the axial space of the embroidery machine head increases. Furthermore, the second transmission point and the presser foot positioning block do not maintain constant contact during the presser foot's working stroke; each contact results in an impact, increasing noise. [Utility Model Content]

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a conjugate cam presser foot drive device and an embroidery machine, thereby solving the problem of increased axial space caused by the simultaneous setting of a first cam and a second cam in existing technologies, while also reducing noise during presser foot operation.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] First, a conjugate cam presser foot drive device is provided, including a conjugate cam mounted on a spindle and a conjugate linkage assembly driven by the conjugate cam. The conjugate cam has an inner cam surface and an outer cam surface. The conjugate linkage assembly includes a conjugate linkage rotatably connected to a first conjugate linkage pin and a presser foot drive linkage rotatably connected to a second conjugate linkage pin. The conjugate linkage has a first transmission part and a second transmission part, and the presser foot drive linkage has a presser foot drive part. The first transmission part cooperates with the inner cam surface, and the second transmission part cooperates with the outer cam surface, so that the conjugate cam drives the conjugate linkage to rotate through the first transmission part and the second transmission part, and the conjugate linkage drives the presser foot drive linkage to rotate. The presser foot drive part is located below the presser foot positioning block, and the presser foot positioning block is connected to the presser foot. When driving the presser foot to work, the presser foot drive linkage is synchronized with the lifting and lowering of the presser foot, so that the presser foot drive part always keeps in contact with the bottom surface of the presser foot positioning block.

[0007] Preferably, the conjugate link includes a first link segment and a second link segment, the first ends of the first link segment and the second link segment are rotatably connected to a first conjugate link pin, and a link angle is formed between the first ends of the first link segment and the second link segment.

[0008] Preferably, the second ends of the first link segment and the second link segment are connected by a connecting segment, and a link adjustment structure is provided between the connecting segment and the second end of the first link segment and / or the second link segment, so as to adjust the link angle.

[0009] Preferably, the connecting section is integrally formed with the first connecting rod section, and the connecting rod adjustment structure includes a fixing hole in the second connecting rod section, an adjustment hole in the connecting section, and a locking screw connecting the adjustment hole and the fixing hole.

[0010] Preferably, the first transmission part is provided with a first roller, and the second transmission part is provided with a second roller. The first roller cooperates with the inner cam surface, and the second roller cooperates with the outer cam surface.

[0011] Preferably, the presser foot positioning block is movably sleeved with the needle bar, the needle bar has a fixed lower stop point above the presser foot positioning block, and a presser foot spring is movably sleeved on the needle bar. The upper end of the presser foot spring abuts against the lower stop point and the lower end abuts against the presser foot positioning block, and the presser foot spring is always compressed during the working stroke of the presser foot.

[0012] Preferably, the conjugate link assembly further includes an intermediate link, the two ends of which are respectively connected to the first ends of the conjugate link and the pressure foot drive link.

[0013] Preferably, the presser foot drive link is a V-shaped link, and the presser foot drive part is located at the second end of the presser foot drive link.

[0014] Preferably, the presser foot drive unit is provided with a third roller.

[0015] In addition, this utility model also provides an embroidery machine, including the aforementioned conjugate cam presser foot drive device.

[0016] The present invention adopts the above technical solution and has the following technical effects:

[0017] This utility model discloses a conjugate cam presser foot drive device, comprising a conjugate cam mounted on a main shaft and a conjugate connecting rod assembly driven by the conjugate cam. The conjugate cam has an inner cam surface and an outer cam surface. The conjugate connecting rod assembly includes a conjugate connecting rod rotatably connected to a first conjugate connecting rod pin and a presser foot drive connecting rod rotatably connected to a second conjugate connecting rod pin. The conjugate connecting rod has a first transmission part and a second transmission part, and the presser foot drive connecting rod has a presser foot drive part. The first transmission part cooperates with the inner cam surface, and the second transmission part cooperates with the outer cam surface, thereby driving the conjugate cam to rotate through the first and second transmission parts, and driving the presser foot drive connecting rod to rotate through the conjugate connecting rod. The presser foot drive part is located below the presser foot positioning block, and the presser foot positioning block is connected to the presser foot. When driving the presser foot, the presser foot drive connecting rod moves synchronously with the lifting and lowering of the presser foot, ensuring that the presser foot drive part is always in contact with the bottom surface of the presser foot positioning block. On the one hand, compared with the existing technology, only one conjugate cam needs to be set, which solves the problem of increased axial space caused by setting the first cam and the second cam at the same time in the existing technology; on the other hand, since the presser foot drive part always keeps in contact with the bottom surface of the presser foot positioning block when the presser foot is working, the collision between the two is avoided and noise is generated, and it is also conducive to increasing the maximum working speed of the spindle.

[0018] These features and advantages of the present invention will be disclosed in detail in the following specific embodiments and accompanying drawings. [Attached Image Description]

[0019] The utility model will be further described below with reference to the accompanying drawings:

[0020] Figure 1 This is a schematic diagram of the embroidery machine head structure in this utility model;

[0021] Figure 2 This is a schematic diagram of the structure of the embroidery machine head in this utility model (the machine head housing is not shown);

[0022] Figure 3 This is a schematic diagram of the conjugate cam presser foot drive device of this utility model;

[0023] Figure 4 This is a schematic diagram of the conjugate cam presser foot drive device of this utility model;

[0024] Figure 5 This is a schematic diagram of the pressure needle rod structure of this utility model;

[0025] Figure 6 This is a schematic diagram of the pressure needle rod structure of this utility model;

[0026] Reference numerals: Conjugate cam presser foot drive device 1, conjugate cam 11, inner cam surface 111, outer cam surface 112, conjugate connecting rod 12, first connecting rod segment 121, second connecting rod segment 122, connecting segment 123, protruding segment 124, first roller 125, second roller 126, clamping structure 127, locking screw 128, first conjugate connecting rod pin 13, second roller 131, inner sleeve 132, second conjugate connecting rod pin 14, intermediate connecting rod 15, presser foot drive connecting rod 16, third roller 161; presser needle rod structure 2, presser rod 2 1. Lower pressing section 211, lifting section 212, lower extension section 213, motor support 22, base plate 221, upright plate 222, cam 23, second torsion spring 24, presser bar motor 25, first torsion spring 26, fulcrum shaft 27; transverse slide rail mechanism 3, machine head housing 4, needle bar frame 5, bottom beam 501, middle beam 502, needle bar 51, embroidery needle 511, presser foot 52, presser foot part 521, presser foot positioning block 53, presser foot positioning part 531, presser foot spring 54, lower stop point 55, needle bar spring 56, drive shaft 6, needle bar driver 7.

Detailed Implementation Methods

[0027] The technical solutions of the present utility model will be explained and described below with reference to the accompanying drawings. However, the following embodiments are only preferred embodiments of the present utility model and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments in the implementation methods without creative effort are all within the protection scope of the present utility model.

[0028] Those skilled in the art will understand that, without conflict, the features in the following embodiments and implementations can be combined with each other.

[0029] The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. For example, terms such as "upper," "lower," "front," "rear," and "lateral," which indicate orientation or positional relationship, are based solely on the orientation or positional relationship shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device / component referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0030] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "fixation," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0031] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0032] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0033] like Figures 1 to 6 As shown, the embroidery machine has at least one machine head, which includes a machine head housing 4 and a needle bar frame 5 located on the front side of the machine head housing. A transverse slide rail mechanism 3 is provided between the needle bar frame 5 and the machine head housing 4. In this embodiment, the relative direction between the needle bar frame 5 and the machine head housing 4 is defined as the front-back direction, and the direction of movement of the needle bar frame 5 is defined as the transverse direction, or the left-right direction. The embroidery machine has a main shaft that extends transversely and passes through each machine head housing. The main shaft serves as a power source to drive the needle bars 51 mounted on the needle bar frame to perform reciprocating lifting and lowering movements, so that the embroidery needles 511 at the bottom of the needle bars can embroider on the embroidery fabric. In addition, when it is necessary to change colors, the needle bar frame 5 slides transversely along the transverse slide rail mechanism 3.

[0034] The needle bar frame 5 has at least one needle bar 51 mounted horizontally. The needle bar frame 51 has a base beam 501 and a middle beam 502 located above the base beam. The needle bar 51 moves through the base beam 501 and the middle beam 502. A needle bar spring 56 is connected to the needle bar 51 above the middle beam. A presser foot 52, a lower stop point 55 located above the presser foot, and a presser foot spring 54 located between the presser foot and the lower stop point are installed on the needle bar 51 between the base beam 501 and the middle beam 502. The lower stop point 55 is fixed to the needle bar. An embroidery needle 511 is provided at the bottom of the needle bar 51. The upper part of the presser foot 52 is movably mounted on the needle bar 51 via a presser foot positioning block 53. The bottom of the presser foot 52 has a presser foot part 521, and the middle of the presser foot 52 has a side recess that crosses the base beam. The side recess can move up and down relative to the base beam 501. The presser foot 52 is connected to a presser foot positioning block 53 and a presser foot spring 54. The presser foot positioning block 53 is nested movably with the needle bar 51. The presser foot positioning block 53 is located below the lower stop point 55. The upper end of the presser foot spring abuts against the lower stop point 55, and the lower end abuts against the presser foot positioning block 53. When the presser foot positioning block 53 drives the presser foot 52 to rise, it presses the presser foot spring 54 upward. When the presser foot positioning block 53 descends, the presser foot spring 54 returns to its original position.

[0035] In addition, the embroidery machine head also includes a drive shaft 6 mounted on the machine head housing 4. The drive shaft 6 is vertically arranged, and a needle bar driver 7 is movably connected to it. The needle bar driver 7 and the lower stop 55 are separated and engaged through a clutch structure. In the engaged state, the needle bar driver 7 drives the lower stop 55 and the needle bar 51 to rise and fall synchronously. In the disengaged state, there is no interaction between the needle bar driver 7 and the lower stop 55.

[0036] like Figure 3 As shown, in this embodiment, the embroidery machine head is equipped with a conjugate cam presser foot drive device 1. The conjugate cam presser foot drive device 1 includes a conjugate cam 11 mounted on the main shaft and a conjugate connecting rod assembly driven by the conjugate cam 11. The conjugate connecting rod assembly is located below the main shaft. The conjugate cam 11 has an inner cam surface 111 and an outer cam surface 112. The conjugate connecting rod assembly includes a conjugate connecting rod 12 rotatably connected to a first conjugate connecting rod pin 13 and a presser foot drive connecting rod 16 rotatably connected to a second conjugate connecting rod pin 14. The conjugate connecting rod 12 has a first transmission part and a second transmission part, and the presser foot drive connecting rod 16 has a presser foot drive part. The first transmission part cooperates with the inner cam surface, and the second transmission part cooperates with the outer cam surface, so that the conjugate cam drives the conjugate connecting rod to rotate through the first and second transmission parts, and the conjugate connecting rod drives the presser foot drive connecting rod to rotate. 。 Furthermore, the first and second transmission parts always act on the inner and outer cam surfaces of the conjugate cam, thereby maintaining the relative position of the conjugate connecting rod assembly.

[0037] like Figure 3 and Figure 4As shown, the presser foot drive unit is located below the presser foot positioning block 53. The presser foot positioning block 53 has a horizontally protruding presser foot positioning part 531 that cooperates with the presser foot drive unit. The presser foot drive linkage 16 is synchronized with the lifting and lowering of the presser foot when driving it to work, so that the presser foot drive unit always maintains contact with the bottom surface of the presser foot positioning block. At the same time, the presser foot spring 54 is always compressed during the working stroke of the presser foot. Specifically, the distance between the lower stop point 55 and the presser foot positioning block 53 is L1, and the free length of the presser foot spring is L2. During the working stroke of the presser foot, L1 is always less than L2, so that the presser foot spring is always compressed. Since the presser foot drive unit always maintains contact with the bottom surface of the presser foot positioning block when the presser foot is working, the collision between the two is avoided, thus reducing the working noise and also helping to increase the maximum working speed of the spindle.

[0038] The aforementioned conjugate cam presser foot drive device has an outer cam surface that cooperates with the second transmission part, causing the presser foot positioning block to drive the presser foot to complete the upward stroke; and an inner cam surface that cooperates with the first transmission part, causing the presser foot positioning block to drive the presser foot to complete the downward stroke. Compared with the prior art, only one conjugate cam needs to be set, which solves the problem of increased axial space caused by setting both the first cam and the second cam in the prior art.

[0039] The conjugate connecting rod 12 includes a first connecting rod segment 121 and a second connecting rod segment 122. The first ends of the first and second connecting rod segments are rotatably connected to a first conjugate connecting rod pin 13, and a connecting rod angle A is formed between the first ends of the first and second connecting rod segments. The first and second transmission parts are disposed on the conjugate connecting rod, and the first conjugate connecting rod pin 13 and the second conjugate connecting rod pin 14 are mounted on the head housing 4. One of the first ends of the first connecting rod segment 121 and the second connecting rod segment 122 is provided with an inner sleeve, and the other is provided with an outer sleeve. The inner sleeve and the outer sleeve are nested inside each other to achieve a rotational fit. In addition, a bearing can be provided between the inner sleeve and the first conjugate connecting rod pin 13 to achieve a smooth rotational fit. The main bodies of the first connecting rod segment 121 and the second connecting rod segment 122 are aligned, so that the first transmission part and the second transmission part are located on the same side of the main bodies of the first connecting rod segment 121 and the second connecting rod segment 122, and the first transmission part and the second transmission part correspond to each other in the axial direction of the conjugate cam 11, and respectively cooperate with the inner cam surface 111 and the outer cam surface 112.

[0040] Furthermore, the second ends of the first connecting rod segment 121 and the second connecting rod segment 122 are connected by a connecting segment 123, and a connecting rod adjustment structure is provided between the connecting segment 123 and the second end of the second connecting rod segment. The connecting rod angle is adjusted by the connecting rod adjustment structure. Specifically, the connecting segment is integrally formed with the first connecting rod segment. The connecting rod adjustment structure includes a fixing hole in the second connecting rod segment, an adjustment hole in the connecting segment, and a locking screw connecting the adjustment hole and the fixing hole. The adjustment hole can be a slotted hole, and the locking screw can move relative to the adjustment hole. The connecting rod adjustment structure facilitates the rotational connection between the first ends of the first and second connecting rod segments and the first conjugate connecting rod pin 13. It also allows the connecting rod angle to be adjusted after the conjugate connecting rod is assembled with related components. Finally, the locking screw is fixed, so that the first and second transmission parts can then form a corresponding engagement with the inner cam surface 111 and the outer cam surface 112.

[0041] To reduce wear and impact during transmission, the first transmission part is provided with a first roller 125, and the second transmission part is provided with a second roller 126. The second end of the first connecting rod segment is connected to the first roller shaft via a clamping structure 127. A bearing can be installed between the first roller body and the first roller shaft. The second roller shaft of the second roller 126 can be connected to a locking screw 128, and a bearing can be installed between the second roller body and the second roller shaft.

[0042] In this embodiment, the presser foot drive unit is provided with a third roller 161, and the presser foot positioning block 53 is provided with a presser foot positioning part 531 protruding above the third roller 161, and the bottom surface of the presser foot positioning part 531 cooperates with the third roller 161.

[0043] When the third roller 161 on the presser foot drive linkage 16 rises, it remains in contact with the bottom surface of the presser foot positioning part 531, causing the presser foot positioning block 53 to rise. When the third roller 161 on the presser foot drive linkage 16 falls, the presser foot can fall under the action of the presser foot spring 54, and the third roller 161 also falls synchronously, always remaining in contact with the bottom surface of the presser foot positioning part 531. That is, the rising of the presser foot relies on the action of the conjugate cam and the conjugate linkage assembly, but the falling of the presser foot mainly relies on the action of the presser foot spring. The conjugate cam and the conjugate linkage assembly still work, causing the third roller 161 to fall synchronously as well. Of course, the presser foot drive linkage 16 can be connected to a return torsion spring to ensure better reset.

[0044] Furthermore, the conjugate link assembly also includes an intermediate link 15, the two ends of which are respectively connected to the first ends of the conjugate link and the pressure foot drive link 16. The second end of the second link segment 122 of the conjugate link has a protruding section 124, which is hinged to the intermediate link 15 via a clamping structure and a link pin.

[0045] In this embodiment, the lateral projection of the main part of the conjugate link 12 is a triangle, with the first link segment 121, the second link segment 122, and the connecting segment 123 corresponding to the three sides. The lateral projections of the first transmission part, the second transmission part, and the first conjugate link pin are respectively located at the three corners of the lateral projection triangle of the conjugate link 12. In this way, within a limited space, the first transmission part, the second transmission part, and the first conjugate link pin are staggered and do not interfere with each other. Furthermore, in the horizontal projection, the first link segment 121, the second link segment 122, and the connecting segment 123 are all located on the same side of the conjugate cam, forming a compact layout in the lateral space and avoiding an increase in axial space.

[0046] In some embodiments, the presser foot drive link 16 is a V-shaped link with a first side and a second side, and the fulcrum connecting to the second conjugate link pin is located at the junction of the first and second sides. Preferably, the first side is shorter than the second side, wherein the first side is connected to the intermediate link 15. Since the presser foot drive link 16 rotates perpendicular to the horizontal plane, designing it as a V-shaped link can save space in the front-rear direction.

[0047] In the existing technology, the needle bar has an upper stop point above the lower stop point. The needle bar stops at the highest position of the needle bar driver and presser foot driver's vertical movement by engaging with the middle beam on the upper needle bar frame through the upper stop point, allowing the lower stop point to engage with the needle bar driver. However, during operation, the upper stop point will collide with the middle beam of the needle bar frame when it is in a limited position, generating noise. To avoid this noise, the applicant proposes to eliminate the upper stop point. The lower stop point is always engaged with the needle bar driver during operation. The maximum working stroke of the needle bar driver ensures that the lower stop point will not collide with the needle bar frame, thus reducing noise during operation. However, this also requires a needle bar pressing structure to press down the needle bar before the lower stop point engages with the needle bar driver, and the bottom surface of the presser foot drive part to engage with the third roller.

[0048] like Figure 5 and Figure 6 As shown, in some embodiments, the needle presser structure 2 includes a needle presser motor 25 and a presser rod 21. The needle presser motor 25 drives the presser rod 21, causing the presser rod to press down the needle bar 51, thereby aligning the needle bar driver 7 with the lower stop point 55 in height. The needle bar driver 7 is connected to the lower stop point 55 and drives the needle bar 51 through the lower stop point 55. Before the needle bar and presser foot work, the needle presser structure 2 works. After the needle presser structure 2 presses down the needle bar 51, the needle bar driver 7 engages with the lower stop point 55 through a clutch mechanism. At the same time, the bottom surface of the presser foot positioning part 531 abuts against the third roller 161, and the needle presser structure 2 resets. Subsequently, the needle bar driver 7 and the conjugate cam presser foot drive device 1 drive the needle bar and presser foot to work respectively.

[0049] Specifically, the pressure rod 21 is rotatably mounted above the needle bar 51. The pressure rod 21 has a pressing section 211 on its first side of its rotation fulcrum for pressing down the needle bar. The output shaft of the needle bar motor is connected to a cam 23. The pressure rod 21 has a lifting section 212 on its second side of the rotation fulcrum. When the needle bar is pressed down, the cam 23 cooperates with the lifting section 212 to drive the lifting section upwards. The pressure rod 21 acts as a lever, rotating around the rotation fulcrum. The cam 23, in cooperation with the lifting section 212, can raise the lifting section while simultaneously pressing down the pressing section 211.

[0050] Furthermore, the pressure rod can be a V-shaped rod, with an included angle between the pressing section and the lifting section. A downwardly extending lower extension section 213 is provided at the connection between the pressing section and the lifting section, and the lower extension section 213 is connected to the fulcrum shaft 27. In this way, the ends of the pressing section, the lifting section, and the lower extension section are essentially at the same height, and the motor can also be installed at a lower height, thus controlling the overall height of the pressure needle rod structure 2. It can be understood that the fulcrum shaft can be a bolt structure.

[0051] Furthermore, the pressure rod 21 is connected to an elastic reset member for raising the lower section. Specifically, the elastic reset member is a first torsion spring 26. This allows for rapid reset of the pressure rod 21. Additionally, the cam 23 may also be connected to a second torsion spring 24.

[0052] Specifically, the pressure bar motor 25 is mounted on a motor support 22, which includes a base plate 221 and a vertical plate 222. The pressure bar motor 25 is mounted on the first side of the vertical plate, the pressure bar 21 is rotatably mounted on the second side of the vertical plate, and the cam 23 is located on the second side of the vertical plate. The base plate is bolted to the upper part of the machine head housing, and the pressure bar structure 2 is fitted with the needle bar.

[0053] It is understood that the connecting rod involved in this embodiment refers to a rod with a similar function but whose shape is not limited to a rod-shaped structure. Bearings or bushings can be provided between the connecting rod and the connecting rod pin.

[0054] The above description is merely a specific embodiment of the utility model, but the scope of protection of the utility model is not limited thereto. Those skilled in the art should understand that the utility model includes, but is not limited to, the content described in the accompanying drawings and the specific embodiments above. Any modifications that do not depart from the functional and structural principles of the utility model will be included within the scope of the claims.

Claims

1. A conjugate cam presser foot drive device, comprising a conjugate cam mounted on a main shaft and a conjugate connecting rod assembly driven by the conjugate cam, characterized in that, The conjugate cam has an inner cam surface and an outer cam surface; the conjugate connecting rod assembly includes a conjugate connecting rod rotatably connected to a first conjugate connecting rod pin and a pressure foot driving connecting rod rotatably connected to a second conjugate connecting rod pin. The conjugate connecting rod has a first transmission part and a second transmission part, and the pressure foot driving connecting rod has a pressure foot driving part. The first transmission part cooperates with the inner cam surface, and the second transmission part cooperates with the outer cam surface, so that the conjugate cam drives the conjugate connecting rod to rotate through the first transmission part and the second transmission part, and the conjugate connecting rod drives the pressure foot driving connecting rod to rotate. The pressure foot driving part is located below the pressure foot positioning block, and the pressure foot positioning block is connected to the pressure foot. When driving the pressure foot to work, the pressure foot driving connecting rod is synchronized with the lifting and lowering of the pressure foot, so that the pressure foot driving part always keeps in contact with the bottom surface of the pressure foot positioning block.

2. The conjugate cam pressure foot drive device according to claim 1, characterized in that, The conjugate link includes a first link segment and a second link segment. The first ends of the first link segment and the second link segment are rotatably connected to a first conjugate link pin, and a link angle is formed between the first ends of the first link segment and the second link segment.

3. The conjugate cam pressure foot drive device according to claim 2, characterized in that, The second ends of the first link segment and the second link segment are connected by a connecting segment, and a link adjustment structure is provided between the connecting segment and the second end of the first link segment and / or the second link segment, so as to adjust the link angle.

4. The conjugate cam pressure foot drive device according to claim 3, characterized in that, The connecting section is integrally formed with the first connecting rod section, and the connecting rod adjustment structure includes a fixing hole in the second connecting rod section, an adjustment hole in the connecting section, and a locking screw connecting the adjustment hole and the fixing hole.

5. The conjugate cam pressure foot drive device according to claim 1, characterized in that, The first transmission part is provided with a first roller, and the second transmission part is provided with a second roller. The first roller is engaged with the inner cam surface, and the second roller is engaged with the outer cam surface.

6. The conjugate cam pressure foot drive device according to claim 1, characterized in that, The presser foot positioning block is movably sleeved with the needle bar. The needle bar has a fixed lower stop point above the presser foot positioning block. A presser foot spring is movably sleeved on the needle bar. The upper end of the presser foot spring abuts against the lower stop point, and the lower end abuts against the presser foot positioning block. The presser foot spring is always compressed during the working stroke of the presser foot.

7. The conjugate cam pressure foot drive device according to claim 1, characterized in that, The conjugate link assembly also includes an intermediate link, the two ends of which are respectively connected to the first ends of the conjugate link and the pressure foot drive link.

8. The conjugate cam pressure foot drive device according to claim 1, characterized in that, The presser foot drive linkage is a V-shaped linkage, and the presser foot drive part is located at the second end of the presser foot drive linkage.

9. The conjugate cam pressure foot drive device according to claim 8, characterized in that, The presser foot drive unit is equipped with a third roller.

10. An embroidery machine, characterized in that, Includes the conjugate cam presser foot drive device as described in any one of claims 1 to 9.

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