Edge covering strip guiding device and edge covering machine

Abstract

The invention relates to an edge covering strip guiding device and an edge covering machine. The edge covering strip guiding device comprises an edge covering cylinder. The edge covering cylinder is provided with a cloth conveying channel for conveying edge covering strips, and a cloth inlet and a cloth outlet are formed in the two ends of the cloth conveying channel. A first rotating shaft is arranged on one side, behind the cloth outlet, of the edge covering cylinder; when the edge covering cylinder exits from the edge covering state, the cloth outlet rotates towards the convex side around the first rotating shaft; and meanwhile, the first rotating shaft moves towards the concave side of the edge covering cylinder in the edge covering state. According to the edge covering strip guiding device, the edge covering barrel quits from the edge covering state through a set of composite motion, the concave side of the cloth outlet always faces the feeding teeth through the composite motion, a sending-out section can be folded in the same mode as a reverse folding section, and therefore the edge covering strip with the uniform width can be formed in the edge covering ending process and the edge covering initial process. The edge is neat, and the surface is flat.

Description

Technical Field

[0001] The invention relates to the technical field of hemming operation in sewing technology, and in particular to an hemming strip guiding device and an hemming machine. Background Art

[0002] Fabric is mainly woven by warp and weft. If the exposed edges of the fabric are not treated, the warp and weft will easily separate, causing the edges of the fabric to fall apart and become burred. Therefore, it is generally necessary to protect the edges of the fabric in a certain way during the sewing process. One of the protective measures is to hem the edges of the fabric.

[0003] It should be noted that the technology of using the hemming tube to realize the folding and feeding of the hemming strip is an existing mature technology. Similar hemming tube structures can be found in Chinese patent documents disclosed in publication numbers CN215668470U, CN213037971U, etc. However, as for the overall hemming technology integrated into the industrial sewing machine, the automated, efficient and stable hemming equipment needs to not only guide the hemming strip, but also handle auxiliary tasks such as cutting the hemming strip, and it is necessary to ensure the efficient and stable operation of the industrial sewing machine.

[0004] In order to ensure the consistency, neatness and beauty of the hemming, it is generally necessary to place the outlet of the hemming tube close to the cloth at the presser foot so that the cloth is inserted into the recess of the hemming tube. At this time, there is actually no working space for cutting between the hemming tube and the presser foot, and neither the hot cutting mechanism nor the cold cutting mechanism has enough movement space. In addition, even if the cutting action can be completed reluctantly, it is actually impossible to guarantee that the cloth to be hemmed will not be cut incorrectly. Therefore, the cutting mechanism is basically designed upstream of the incoming material of the hemming tube, or integrated on the conveying path of the hemming strip on the hemming tube. If the cutting mechanism is designed upstream of the hemming tube, although the cutting task can be achieved, it involves the problem of re-loading the hemming strip, so it is difficult to apply in automated mass production. The solution of integrating the cutting mechanism on the conveying path of the hemming strip on the hemming tube has been disclosed by the Chinese patent document with publication number CN218756418U. However, it should be noted that since the hemming tube is gradually deformed and narrowed along the discharge direction, and its cross section is curved in the middle process, the applicant found that it is difficult to ensure that the hemming strip is stably cut through the cooperation between the moving knife and the hemming tube wall, and on the other hand, the hemming strip after cutting may still be blocked in the hemming tube due to the influence of the narrowed hemming tube surface, which seriously affects the continuity of operation and production efficiency. Therefore, similar solutions are also difficult to be widely used in industrial sewing machines.

[0005] As far as the applicant's practice is concerned, it is still preferred to set a cutting mechanism downstream of the edging tube (i.e. outside the outlet of the edging tube along the direction of the edging strip being fed out), so that the edging strip is always in the edging tube before and after cutting, and there is no problem of feeding reliability.

[0006] Based on this, the applicant applied for a Chinese patent related to the hemming tube, with application number 202410713883.4, titled "Hemming tube assembly and hemming machine", which has been published. In order to realize the arrangement of the cutting mechanism, in the technical solution of the above patent, the applicant provided a technical solution of a controlled moving hemming tube. When cutting is required, the hemming tube is moved to provide space for the operation of the cutting mechanism.

[0007] Even so, the hemming tube in the above scheme mainly reciprocates in linear motion, and according to the actual situation, its linear motion direction is basically perpendicular to the hemming direction of the fabric. In fact, the hemming strip will go through a flipping and folding process after it leaves the hemming tube outlet, so when the hemming tube retreats linearly, its original flipping position will not change again, that is, the hemming strip that continues to be exposed outside the hemming tube outlet as the hemming tube retreats is not folded, and if it continues to be used for hemming sewing, it will form obvious unsightly folding and wrinkles at the end of the hemming.

[0008] The contents of the prior art cited in the above background technology are regarded as the contents recorded in this application based on the reference. Summary of the invention

[0009] In view of the fact that the hemming tube in the prior art has a poor finishing effect after completing one round of hemming, resulting in appearance problems such as turning inside out, wrinkles, and uneven width of the hemming at the end of the hemming and the beginning of the next round of hemming, the present invention provides an hemming strip guiding device and an hemming machine.

[0010] The technical solution of the present invention provides an edge strip guiding device, including an edge strip guiding tube; The hemming tube has a cloth feeding channel for conveying the hemming strips, and a cloth inlet and a cloth outlet are formed at both ends of the cloth feeding channel; The cloth feeding channel at the cloth outlet has a U-shaped cross section, and the concave side of the hemming tube is defined based on the direction of the inner concave surface of the U-shaped cross section, and the convex side of the hemming tube is defined based on the direction of the outer convex surface of the U-shaped cross section; In the hemming state, the front is defined by the direction of material discharge from the cloth outlet; the rear is defined by the opposite direction of material discharge from the cloth outlet; The hemming tube has a first rotating shaft at one side behind the cloth outlet; When the hemming tube exits the hemming state, the cloth outlet rotates around the first rotating axis toward the convex side; and at the same time, the first rotating axis moves toward the concave side of the hemming tube in the hemming state, so that when the hemming tube rotates, there is at least a translational component toward the concave side of the hemming tube in the hemming state, thereby ensuring that the hemming strip always flows out along the reverse wrapping channel when the hemming tube exits the hemming state.

[0011] Preferably, the hemming strip guiding device comprises a fixed guiding component and a movable component; The movable component comprises an edge-binding tube and a rolling component rollingly arranged on the guide component; in the movable component, the rolling component is transmission-connected with the first rotating shaft of the edge-binding tube, and the first rotating shaft is fixedly connected with the edge-binding tube.

[0012] Preferably, when exiting the hemming state, the hemming tube moves upward along the axial direction of the first rotating shaft.

[0013] Preferably, the hemming strip guiding device comprises a fixed guiding component and a movable component; The movable component includes an edge-binding tube and a rolling component rollingly arranged on the guide component; the rolling component is drivingly connected to the first rotating shaft of the edge-binding tube, and the edge-binding tube is circumferentially fixed to the first rotating shaft; The movable component includes a supporting surface arranged below the edging tube, the lower surface of the edging tube is arranged in contact with the supporting surface, and an elastic component is arranged between the edging tube and the movable component, and the elastic component presses the edging tube against the surface of the supporting surface along the axial direction of the first rotating shaft.

[0014] Preferably, the movable component is coaxially and fixedly connected to the first rotating shaft.

[0015] Preferably, when the hemming tube exits the hemming state, the rolling component rolls along an arc path on the guide component to cause the movable component to rotate toward the concave side of the hemming tube in the hemming state.

[0016] Preferably, the movable component is provided with a swing arm, one end of which is rotatably provided at a second rotating shaft, the rolling component is rotatably provided on the swing arm and rollingly cooperates with the guide component; the center of the arc path coincides with the second rotating shaft.

[0017] Preferably, when the hemming tube exits the hemming state, the rolling component rolls on the guide component along a straight path to make the movable component translate toward the concave side of the hemming tube in the hemming state.

[0018] Preferably, the guide component is a rack, the movable component is a gear, and the gear meshes and rolls on the rack.

[0019] Preferably, the movable component includes a driving device for driving the movable component to roll.

[0020] Preferably, the driving device and the rolling assembly are coaxially fixed.

[0021] Preferably, the driving device is coaxially arranged with the second rotating shaft, and the driving device is transmission-connected with the rolling assembly.

[0022] Preferably, a check plate is provided in the cloth feeding channel of the hemming tube, and the check plate is used to prevent the hemming strip from retreating in a direction opposite to the conveying direction.

[0023] Preferably, the non-return sheet is an elastic sheet, and one end of the elastic sheet is pressed against the edge strip along the conveying direction of the edge strip.

[0024] Preferably, it further comprises a shearing mechanism, wherein the shearing mechanism has a shearing component capable of controlled movement; When the hemming tube exits the hemming state, the shearing assembly moves to contact the hemming strip and cuts off the hemming strip.

[0025] The present invention also provides an edge binding machine, comprising the edge binding strip guiding device described in any one of the above items.

[0026] Preferably, a reciprocating feed tooth is provided on the needle plate of the hemming machine, the hemming strip guide device is arranged behind the feed tooth, and the hemming tube extends forward to the feeding side of the feed tooth in the hemming state.

[0027] Preferably, a guide is fixedly arranged on the needle plate, and the guide is located between the feed tooth and the cloth outlet of the forwardly extending hemming tube, and the guide is used for guiding the hemming strip after being cut.

[0028] In the hemming strip guiding device of the present invention, the hemming tube exits the hemming state through a group of composite motions, specifically, a composite of the hemming tube's own rotation around the first rotating axis and the movement of the first rotating axis toward the concave side of the hemming tube. The rotation of the hemming tube causes the cloth outlet to move toward the convex side and retreat at the same time, and the movement of the first rotating axis toward the concave side causes the hemming tube as a whole to have a moving component toward the concave side, thereby reducing the displacement of the cloth outlet on the convex side.

[0029] This compound movement makes the concave side of the cloth outlet always face the feed dog, so that the delivery section can naturally complete the flipping of the folding surface of the hemming strip and naturally concave in the turn-back channel to form the same folding method as the reverse folding section under the force of pulling during the whole process of the hemming tube movement. Therefore, a hemming appearance with uniform width, neat edges and smooth surface can be formed in the finishing process and the initial process of hemming. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the hemming tube in the prior art; Figure 2 It is a schematic diagram of feeding the hemming tube during single-layer hemming in the prior art; Figure 3 It is a schematic diagram of feeding the hemming tube during double-layer hemming in the prior art; Figure 4 It is a schematic diagram of the working of the hemming tube in the prior art during double-layer hemming; Figure 5 A schematic diagram of a swaging tube that is movable in the prior art; Figure 6 It is a structural schematic diagram of the edge strip guiding device 1 of the present invention; Figure 7 A schematic diagram of the movement of the edge strip guide device 1 of the present invention; Figure 8 The motion simulation data of an embodiment of the hemming strip guiding device 1 of the present invention; Fig. 9 It is a structural schematic diagram of an embodiment of the hemming tube 3 in the hemming strip guiding device 1 of the present invention; Fig.10 It is a structural schematic diagram of the hemming strip guiding device 1 with a shearing mechanism 34 in the present invention; Fig.11 It is a structural schematic diagram of an edge binding machine having an edge binding strip guiding device 1 in the present invention; Fig.12 It is a partial enlarged schematic diagram of the hemming machine at the machine head in the present invention; Fig.13 It is a structural schematic diagram of another embodiment of the edge strip guiding device 1 of the present invention; Fig.14 It is a structural schematic diagram of another embodiment of the edge strip guiding device 1 of the present invention; Fig.15 It is a structural schematic diagram of another embodiment of the edge strip guiding device 1 of the present invention; Fig.16 The edge strip guide device 1 of the present invention Fig.15 A schematic diagram of a multi-link mechanism 4 of an embodiment; Fig.17 It is a schematic diagram of the hemming tube of the hemming strip guiding device 1 of the present invention.

[0031] In the figure: 1: hemming strip guide device; 11: guide assembly; 12: rolling assembly; 13: movable assembly; 131: swing arm; 132: support surface; 133: elastic assembly; 134: rotating assembly; 1341: spiral guide groove; 135: fixed assembly; 14: driving device; 2: hemming machine; 21: presser foot; 22: sewing needle; 23: needle plate; 24: feed dog; 25: guide; 3: hemming tube; 31: cloth feeding channel; 311: cloth inlet; 312: cloth outlet; 3121: side; 3 122: spine; 3123: reverse wrapping channel; 3124: material blocking groove; 313: check plate; 32: serpentine bracket; 33: pressing plate; 34: shearing mechanism; 341: shearing assembly; 342: hot cutting knife; 343: sliding shaft; 4: multi-link mechanism; 41: connecting rod; 42: rocker; 421: sliding groove; 422: fixed end; F: movement direction; O: first rotating shaft; O2: second rotating shaft; W: hemming strip; W1: guiding section; W2: feeding section; W3: folding section; WW: main fabric. DETAILED DESCRIPTION

[0032] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. In this specification, the size ratios in the drawings do not represent the actual size ratios, but are only used to reflect the relative position relationship and connection relationship between the components. Components with the same name or the same number represent similar or identical structures and are only for illustrative purposes.

[0033] Figure 1 The structural diagram of the hemming tube 3 in the prior art (see Figure 1-5 All are perspective views, not orthogonal views). The hemming tube 3 is not only used to guide the hemming strip W to the front of the presser foot of the sewing machine head, but also used to limit the hemming strip W to the folded shape required for hemming, so that the hemming strip W can be neatly and reliably sewn to the edge of the main fabric WW. In order to achieve the above purpose, the hemming tube 3 usually includes a cloth feed channel 31. In the prior art, as shown in sections AA and BB, the cloth feed channel 31 has a cloth inlet 311 and a U-shaped cloth outlet 312. As shown in section CC, the cloth outlet 312 has a certain inclination angle relative to the cloth feeding direction of the cloth feed channel 31. The existence of the inclination angle makes the cloth outlet 312 not only have a U-shaped cross-section (AA cross-section) in the cloth feeding direction, but also have a U-shaped cross-section (DD cross-section) when viewed in the direction of the U-shaped opening. Reference Figure 1 Under the setting of the inclination angle, the cloth outlet 312 will form conical contracted side portions 3121 located on both sides and a concave ridge portion 3122 located between the two side portions, and obviously form a turn-up channel 3123 formed by the side portions 3121. In addition to the cloth inlet 311 of the hemming tube 3, a serpentine bracket 32 ​​is optionally provided to flatten the hemming strip W and feed it into the cloth inlet 311.

[0034] Figure 2 for Figure 1 Schematic diagram of feeding the hemming tube 3 during single-layer hemming. Figure 2 In the schematic diagram of the incision after sewing, the so-called single-layer edging refers to the edging strip W being folded in half (not necessarily symmetrically), and the edge of the main fabric WW is sandwiched between the two layers of the folded edging strip W. The edge of the main fabric WW is protected by the edging strip W, which can basically eliminate problems such as edge loosening. If there is a serpentine bracket 32 ​​for the single-layer edging, the edging strip W from the roll storage alternately passes through the gap of the serpentine bracket 32 ​​at the guide section W1 and advances in an S shape. In the process of advancing, it can be gradually flattened and the folding of the edging strip W in advance can be avoided. In the cloth feed channel 31 whose cross-section gradually changes to a U-shape, the edging strip W is shaped by the cloth feed channel 31 to form a U-shaped cross-section and is delivered from the cloth outlet 312. Referring to the schematic diagram of the folding of the edging strip, the edging strip W is turned over after being delivered from the cloth outlet 312 and is reversed to be delivered along the turned-over channel 3123 of the cloth outlet 312. The turn-over here can refer to Figure 2 There is a schematic diagram of the hemming tube 3 in the figure. When the hemming strip W is sent out of the cloth outlet 312, it folds toward one side surface to form an inner folding surface (the normal direction of the inner folding surface points to the inside of the U-shaped cross section and is concave into the reverse wrapping channel 3123). However, when the hemming strip W passes through the reverse wrapping channel 3123, the hemming strip W will experience a process of being squeezed and retracted from the center to the ridge 3122. The squeezing force is generally provided by the main cloth WW, while the edge portion of the hemming strip W located at the side 3121 will not be retracted. After this deformation, the original inner folding surface is flipped to the outer folding surface of the reversed section W3, that is, the inner folding surface and the outer folding surface are flipped. And the movement direction F of the hemming strip W is naturally switched from extending along the normal direction of the cloth outlet 312 through the angled bevel cut of the cloth outlet 312 to moving along the normal direction of the reverse wrapping channel 3123 or approximately along the normal direction of the reverse wrapping channel 3123 after reverse wrapping.

[0035] Figure 3 for Figure 1 Schematic diagram of feeding the hemming tube 3 during double-layer hemming. Figure 3 The incision after sewing in the figure is shown in the figure. The so-called double-layer hemming refers to the Figure 2 On the basis of the single-layer edging shown, the edge of each side of the edging strip W is folded toward the inside of the U-shape, and the edge of the edging strip W is also hidden inside the edging for protection. At this time, the edging strip W has a four-layer structure at the folded section W3. Figure 3 The general structure of the double-layer hemming tube 3 is Figure 2 They are basically the same, the difference is that, for double-layer edging, the shrinkage ratio between the cloth inlet 311 and the cloth outlet 312 of the cloth feed channel 31 is different, and additional guide edges and other structures may be formed in the cloth feed channel 31, so that when the edging strip W is fed out of the cloth outlet 312, it has a secondary folded cross-sectional shape required for double-layer edging.

[0036] Figure 4 The figure is a schematic diagram of the working of the hemming tube 3 during double-layer hemming (the light-colored line is the part covered by the main fabric WW). During the hemming sewing process, the main fabric WW and the reversed section W3 are continuously advanced by the feed dog 24. In order to make the hemming strip W neatly and stably positioned at the edge of the main fabric WW and evenly cover the edge of the main fabric WW during the sewing process, during sewing, the cloth outlet 312 of the hemming tube 3 extends forward to the front of the feed dog 24, so that the edge of the main fabric WW about to enter the feed dog 24 enters the reversed channel 3123 and is wrapped by the reversed section W3. At this time, the side portion 3121 on one side is located above the main fabric WW, and the main fabric WW on the other side is located below the main fabric WW. The reciprocating motion of the feed dog 24 cooperates with the presser foot 21 to drive the hemming strip W and the main fabric WW to move together. In this case, the hemming strip W is continuously fed along the motion direction F, and continuously transformed into the reversed section W3 after being fed out of the cloth outlet 312. During this sewing, it is basically stable.

[0037] The applicant disclosed a movable hemming tube 3 in the Chinese patent document entitled “Hemming tube assembly and hemming machine” with application number 202410713883.4, and its schematic diagram is shown in FIG. Figure 5 When the hemming is finished and the cutting operation is performed, the hemming tube 3 generally moves in the opposite direction F2 of the feeding direction of the hemming strip W and exits the front of the feed dog 24. At this time, due to the retreat of the hemming tube 3, a feeding section W2 that exposes the cloth outlet 312 is formed between the feed dog 24 and the cloth outlet 312, and a space between the presser foot 21 and the cloth outlet 312 is provided for the corresponding cutting mechanism to move. The cutting mechanism cuts the hemming strip W at the feeding section W2. When the hemming operation is restarted, the hemming tube 3 extends forward to the cloth outlet 312 and is located in front of the feed dog 24, and clamps the main cloth WW in the reverse wrapping channel 3123 between the side parts 3121.

[0038] Based on the above-mentioned prior art, those skilled in the art know that beautiful and neat hemming depends on the stable and consistent folding of the hemming strip W during the continuous feeding process. First, it is necessary to stably ensure that the hemming strip W stably forms the folded section W3 used in sewing, that is, to ensure that the hemming strip W can achieve the expected folding. Secondly, it is also necessary to form a uniform and consistent crease position on this basis, otherwise the edge of the hemming may be wavy, wide or narrow.

[0039] Figure 5The original intention of the technical solution is to move the hemming tube 3 to leave space for the operation of the cutting mechanism, so as to cut the hemming strip W in the delivery section W2 in front of the cloth outlet 312. In this way, after cutting, the hemming strip W still passes through the cloth feeding channel 31, and there is no problem of unstable feeding caused by re-feeding. However, other derived problems were not considered at the beginning of the design of this solution, that is, how to ensure that the hemming strip W forms a preset folded shape for hemming during the movement of the hemming tube 3. The development process of this technical solution mainly focuses on the cutting problem. When designing the movement of the hemming tube 3 to provide the corresponding cutting space, the technicians in this field assume that the movement of the hemming tube 3 will not affect the shape formation of the hemming strip W, and naturally will not make targeted improvement designs for this.

[0040] In addition, in the design Figure 5 When considering the technical solution, those skilled in the art proposed the use of an additional deflection mechanism to allow the cloth outlet 312 of the hemming tube 3 to appropriately deflect toward the feed dog 24 during the process of extending forward, so that "the hemming strip at the front end of the hemming tube bypasses the presser foot and enters between the presser foot and the needle plate in a swinging manner, which is conducive to the hemming strip directly contacting the product to be processed at one time". This actually also assumes that it is only necessary to ensure that the hemming strip enters the preset position after cutting. The deflection movement given here is more about making the hemming strip W move toward the side of the feed dog 24 when it contacts the main fabric WW, so that it can be smoothly fed between the feed dog 24 and the presser foot 21 along the feeding direction of the main fabric WW. That is to say, when the scheme is formed, it is believed that as long as the hemming strip W can enter the sewing position, the hemming operation can be carried out, and it is assumed that the shape of the hemming strip W entering the sewing operation is in line with expectations.

[0041] However, during the debugging of the prototype, it was found that the technical solution did not work as expected because the technical solution only focused on the layout of the shearing mechanism, but completely ignored the impact of dynamically adjusting the position of the hemming tube 3 on the shape of the hemming strip W.

[0042] refer to Figure 5 , when all the technologies are put on the table, we obviously notice that the delivery section W2 has a different extension direction and folding direction than the rebend section W3. The reason why the delivery section W2 and the rebend section W3 can be switched is that, on the one hand, the rebend channel 3123 opened to the side of the feed dog 24 formed by the angled design at the cloth outlet 312 is also due to the feed dog 24 driving the edge strip W and the main cloth WW to move, so that the edge strip W is continuously pushed along the movement direction F. Due to the pulling of the feed dog 24 on the edge strip W, the edge strip W is bound to deform in this direction. At this time, the edge strip W is supported by the side 3121 and the ridge 3122 at the black triangle position shown in the figure, so it is naturally confined in the rebend channel 3123, and the outer folding at the delivery section W2 is transformed into the inner folding at the rebend section W3.

[0043] If we think about it further, when the hemming tube 3 retreats, the delivery section W2 is exposed. At this time, the delivery section W2 is not supported by the hemming tube 3, which is why it can be cut at the delivery section W2. Considering the situation after cutting, the inverted section W3 can continue to be sewn, but the cut delivery section W2 segment no longer has the support of the hemming tube 3 as shown in the figure, so it is obviously impossible to spontaneously complete the switch from the outer folding of the delivery section W2 to the inner folding of the inverted section W3. In other words, when the hemming finishing work continues, the delivery section W2 will not be able to be wrapped around the edge of the main fabric WW in the expected folding manner like the inverted section W3. The delivery section W2 may extend outward from the edge of the main fabric WW as shown in the figure to form a tail. When the corrector for the hemming strip W is added, it can indeed prevent the hemming strip W from extending outward, but it still cannot guarantee that the delivery section W2 can spontaneously transform into an inward folded shape like the inward folded section W3. Therefore, at this time, the delivery section W2 is more squeezed on the surface of the main fabric WW and sewn in a random shape, which forms obvious wrinkles and an uneven feel on the edge of the surface of the main fabric WW, and cannot form an effective hemming starting section.

[0044] Consider restarting the hemming process. The first problem is that the power for the continuous feeding of the hemming strip W comes from the reciprocating motion of the feed dog 24. However, the delivery segment W2 that is still on the hemming tube 3 after being cut is actually impossible to be driven by the feed dog 24 in the early stage, because the delivery segment W2 and the feed dog 24 are not in contact with each other. At this time, when the hemming tube 3 is extended forward, it is uncertain whether the delivery segment W2 can follow the extension or will retract accordingly. During the debugging process, sometimes due to the large friction between the hemming strip W and the hemming tube 3, and the overall looseness of the hemming strip W between the hemming tube 3 and the material roll, the margin is sufficient, and the delivery segment W2 may extend forward with the hemming tube 3. However, there is also a retraction situation. In the worst case, the delivery segment W2 has retracted into the cloth feeding channel 31.

[0045] Even if the delivery section W2 does not retract, it is difficult to achieve the expected technical effect. The delivery section W2 generally extends outward along the cloth outlet 312 (the U-shaped cross section has a certain support, which can ensure that the delivery section W2 maintains a certain distance of extension). Therefore, when extending forward, the delivery section W2 is more likely to be piled up against the edge of the main cloth WW, and then gradually enters the feed dog 24 to be sewn under the continuous friction of the main cloth WW. Although it can be sewn to form a hemming in the end, in the early stage, the accumulated hemming strips W do not form a stable inverted section W3, so the hemming formed will be loose, wrinkled, with uneven edges and uncertain width. Even if the deflection scheme is added, the delivery direction of the delivery section W2 does not change, and the position where the hemming tube 3 finally stops does not change. Therefore, the deflection mechanism is difficult to achieve the expected effect of facilitating the delivery section W2 to enter the feed dog 24 and the presser foot 21.

[0046] Figure 6 Schematic diagram of the structure of the hemming strip guide device 1 of the present application. In order to avoid the problems caused by the front and rear linear motion of the hemming tube 3, the hemming strip guide device 1 of the present application provides the function of allowing the hemming tube 3 to move in translation and rotation at the same time. Figure 1 , for the hemming tube 3, we define the front and rear directions according to the delivery direction of the hemming strip W, specifically, the direction in which the hemming strip W is delivered from the cloth outlet 312 is defined as the front. That is to say, referring to this definition, the cloth inlet 311 is located behind the cloth outlet 312. In addition, since the cloth feeding channel 31 of the hemming tube 3 has a U-shaped cross-section at the cloth outlet 312, and obviously makes the hemming tube 3 have an outer convex surface and an inner concave surface, accordingly, we define the side to which the inner concave surface of the cloth feeding channel 31 of the hemming tube 3 points as the concave side, and correspondingly, the opposite side is the convex side. Obviously, during the hemming operation, the sewing mechanisms such as the feed dog 24 are located on the concave side of the cloth outlet 312, and the reversed section W3 that flows out of the cloth outlet 312 and changes direction from the reverse wrapping channel 3123 actually also flows out from the concave side to between the feed dog 24 and the presser foot 21.

[0047] The hemming strip guiding device 1 includes a movably arranged hemming tube 3, on which there is a first rotating shaft O, which is located at the rear side of the cloth outlet 312. The hemming tube 3 rotates around the first rotating shaft O, and the rotating direction is defined as making the cloth outlet 312 rotate toward the convex side of the cloth outlet 312 relative to the first rotating shaft O. In addition, when the hemming tube 3 rotates, the first rotating shaft O can move toward the side to which the concave side points when the hemming tube 3 starts to rotate (here, it means that there is at least a translational component in this direction).

[0048] refer to Figure 7The schematic diagram shows the changing trajectory T1 of the hemming strip W during the movement of the hemming tube 3. The figure also shows the trajectory T2 of the cloth outlet 312 making a circular motion around the initial position of the first rotation axis O as a reference. Considering the process of the hemming tube 3 moving from a stable hemming position, i.e., the hemming state, to a certain position and stopping, under the combined movement of the movement of the first rotation axis O and the rotation of the hemming tube 3, the cloth outlet 312 retreats to the rear on the one hand, and continuously rotates to its convex side on the other hand. Since the hemming strip W is pressed by the feed dog 24, the retreat will cause the cloth outlet 312 of the hemming tube 3 to continue to spit out W to form an unsewn delivery section W2. During this process, the distance between the cloth outlet 312 and the inflected section W3 is still expanding, so the delivery section W2 is always pulled by the inflected section W3. In addition, we also noticed that during the rotation, the concave side of the cloth outlet 312 is always facing the inflected section W3. In other words, under the pulling action, the delivery section W2 must have the shortest possible path connecting the cloth outlet 312 and the inflected section W3 as shown in the figure. Referring to the detailed design of the cloth outlet 312, this allows the delivery section W2 to naturally complete the flipping of the folded surface of the edging strip W and naturally recess into the inverted channel 3123 during the entire movement of the edging tube 3 under the force of the pulling action. Fig.17 As shown, the edging tube 3 has a material stopping groove 3124 extending outwardly in the direction of the turned-up channel 3123 on the concave side, and has a groove portion extending from the turned-up channel 3123 and raised edges on both sides of the groove portion. The edges on both sides block the turned-up cloth strips in the material stopping groove 3124 to prevent the turned-up cloth strips from deviating to the sides of the material stopping groove 3124.

[0049] The motion control of this scheme achieves two main purposes. First, it ensures that the delivery segment W2 formed at this time has the same folding mode extending from the reversed segment W3, which is essentially different from the delivery segment formed by the reciprocating motion mechanism in the prior art, which is different from the reversed segment W3. Second, it ensures that the delivery segment W2 formed at this time must naturally enter the reversed channel 3123, not only forming a reversed folding shape that is no different from the hemming operation, but also the delivery segment W2 naturally extends from the reversed channel 3123, completing the reversal.

[0050] Considering the first point, when the delivery section W2 is cut somewhere in the middle, a part of it is connected to the reversed section W3. When the hemming is finished, as the sewing proceeds, this section of the delivery section W2 continues to be sewn to the edge of the main fabric WW. Since the delivery section W2 has the same folding shape as the reversed section W3, it can be stably and evenly fed in during the sewing process with the operation of the feed dog 24, thereby forming a hemming finish with uniform width, neat edges, and a flat surface. However, in the prior art, since the folding directions between the delivery section W2 and the reversed section W3 are opposite, there is a lack of technology to complete the reverse wrapping of the delivery section W2 during the process of continuing to sew the hemming, so as mentioned above, it obviously does not have the technical effect of the technical solution of the present application.

[0051] Considering the second point, when the delivery segment W2 is cut somewhere in the middle, a part of it is exposed from the cloth outlet 312, and due to the pulling effect before being cut, it has spontaneously recessed into the turn-back channel 3123 after exposing the cloth outlet 312. It has not only completed the reversal, that is, from pointing to the front of the cloth outlet 312 when flowing out of the cloth outlet 312 to pointing to the concave side of the cloth outlet 312 after passing through the turn-back channel 3123, but also completed the turn-back, so that the delivery segment W2 flowing out from the turn-back channel 3123 has the same folded shape as the inverted segment W3. At the beginning of the next round of hemming operation, the hemming tube 3 is reset. At this time, since the delivery segment W2 has the same folding shape as the required inverted segment W3 and extends toward the concave side of the cloth outlet 312, at the end of the resetting process, the delivery segment W2 is basically consistent in direction with the edge of the main cloth WW and in direction of movement. Since the delivery segment W2 already has the required folding shape, it can be smoothly connected between the feed dog 24 and the presser foot 21, ensuring the stability and reliability of the hemming startup process. Based on the reasons basically consistent with those mentioned at the end, the neatness and beauty of the starting position of the hemming is also guaranteed.

[0052] There is also a third point, that is, due to the existence of the translational motion component when the first rotating shaft O moves, compared with directly designing the hemming tube 3 as a rotation trajectory T2 around a fixed axis, the trajectory T1 of the cloth outlet 312 of the present technical solution is obviously flatter, which has many advantages. First, given that the hemming tube 3 is generally installed on the needle plate 23, its position is biased towards the side where the feed dog 24 feeds the fabric and the convex side faces outward, and therefore it is closer to the edge of the needle plate 23. The overly protruding trajectory T2 has actually exceeded the space that can be covered and shielded by the sewing machine body, and may bring potential hidden dangers during the movement, such as accidental injury to the operator's limbs. Furthermore, if it simply rotates around a fixed axis, according to Figure 7From the diagram, it can be found that although the distance from the folded section W3 to the cloth outlet 312 is also expanding, the pulling effect can be achieved. However, the angle between the delivery section W2 and the edging tube 3 has a tendency to become sharp during the rotation process, which will have an adverse effect on the folding of the edging strip W at the folding channel 3123. In contrast, although the angle change of the technical solution of the present application fluctuates during the movement, it is not so obvious in fact. Finally, the advantage of a flatter trajectory and being closer to the needle plate 23 is that it is convenient to layout the shearing mechanism, and the working stroke of the shearing mechanism can be reduced and controlled in the space where the needle plate 23 is located. Once it is designed to rotate around a fixed axis, the shearing mechanism has to use a large moving stroke to extend to the trajectory T2 outside the needle plate 23 to cut the edging strip W.

[0053] Figure 6 It is also a schematic diagram of a specific embodiment of the present application. In this embodiment, the movement of the first rotating shaft O and the rotation of the hemming tube 3 are associated through a set of mechanical mechanisms. Specifically, the hemming strip guiding device 1 includes a fixed guide assembly 11 and a movable assembly 13, the movable assembly 13 includes a rolling assembly 12 rollingly arranged on the guide assembly 11, the movable assembly also includes the hemming tube 3, and in the movable assembly 13, the rolling assembly 12 is connected to the first rotating shaft O of the hemming tube 3 in a transmission manner, and has a fixed transmission ratio. The first rotating shaft O is fixed on the hemming tube 3. Therefore, when the rolling assembly 12 rolls on the guide assembly 11, not only the movement of the first rotating shaft O to the concave side of the initial position of the cloth outlet 312 is realized through the movement of the movable assembly 13, but also the rotation of the first rotating shaft O is realized synchronously, which is equivalent to the rotation of the hemming tube 3. This scheme simultaneously fixes the movement relationship between the rolling assembly 12 and the hemming tube 3, thereby solidifying the movement trajectory of the cloth outlet 312, which is conducive to ensuring the stability of the system operation.

[0054] Figure 6 In the embodiment, the movable assembly 13 is coaxially fixedly connected with the first rotating shaft O, which is a special case of transmission connection and is equivalent to a fixed 1:1 transmission ratio between the two. In addition, in order to simplify the transmission mechanism design as much as possible, especially to simplify the matching relationship between the guide assembly 11 and the rolling assembly 12. Figure 6In the optimal embodiment, the guide assembly 11 extends along an arc path, and the arc axis of the guide assembly 11 is the second rotating shaft O2. The movable assembly 13 is provided with a swing arm 131, one end of which is rotatably arranged at the second rotating shaft O2, and the rolling assembly 12 is rotatably arranged at the other end of the swing arm 131 and rolls with the guide assembly 11. Under this scheme, since the arc paths of the swing arm 131 and the guide assembly 11 are concentric, the swing arm 131 can ensure the normal contact and transmission between the guide assembly 11 and the rolling assembly 12 during the movement, and there is no need to set other accessories such as limit mechanisms to limit and ensure the rolling cooperation between the rolling assembly 12 and the guide assembly 11. At this time, the movement path of the first rotating shaft O is an arc, but it is undeniable that it has a component of movement to the concave side when the edging tube 3 is in the initial position. The guide assembly 11 and the rolling assembly 12 are preferably gear meshing, wherein the guide assembly 11 is a rack and the rolling assembly 12 is a gear meshing with it. Specifically in the above embodiment, since the guide assembly 11 has an arc path, the guide assembly 11 in this case can be a rack extending from the arc path. In order to drive the movable assembly 13 and the edging tube 3 to move, the rolling assembly 12 is usually used as an active assembly in the motion coordination, and the driving device is connected to the rolling assembly 12 by transmission. The driving device and the rolling assembly 12 are coaxially fixed, such as a coaxially fixed stepper motor. However, considering that the guide assembly 11 is located at the moving end of the swing arm 131, the mass of the excessively large moving assembly will lead to a large moment of inertia, which is not conducive to the motion control and high-speed operation of the equipment. Therefore, the driving device such as the stepper motor is usually coaxially arranged at the second rotating shaft O2, and the driving device and the rolling assembly 12 are connected by a transmission system to achieve the driving, and the transmission system is such as a synchronous belt connecting the rotating shaft of the driving device and the rotating shaft of the rolling assembly 12.

[0055] For the preferred embodiment, Figure 8 The results after motion simulation are given, and the mechanism parameters used for motion simulation are: the swing arm 131 is 115mm long, the rolling component 12 has a radius of 16mm, the cloth outlet 312 in the edging tube 3 is 35mm away from the first rotating axis O, and the rolling component 12 is meshed with the guide component 11. Since the edging tube 3 has a certain eccentricity relative to the first rotating axis O on the movable component 13, the cloth outlet 312 in the initial position is not located on the x-axis. The angle of the cloth outlet 312 in the initial position relative to the x-axis is about 20 degrees (0.1rad). According to actual conditions, the rotation of the edging tube 3 generally does not exceed 90 degrees (1.57rad). The left figure shows the motion trajectory of the cloth outlet 312 with the second rotating axis O2 as the origin and the front-to-back direction as the x-axis. This is consistent with Figure 7In addition, the middle figure is a schematic diagram of the length of the delivery section W2 when the hemming tube 3 rotates from 20 degrees to 90 degrees, which generally increases linearly, indicating that the delivery section W2 can always receive the pulling effect, remain in the reverse wrapping channel 3123 and have a predetermined folded shape. The right figure shows a curve of the change in the angle between the delivery section W2 and the cloth feed channel 31 when the hemming tube 3 rotates from 20 degrees to 90 degrees. The angle only increases from 1.57 rad to 1.77 rad, that is, the actual variation range of the angle is about 90-100 degrees. This is basically a state in which the side facing the reverse wrapping channel 3123 relative to the cloth feed channel 31 is approximately at a right angle. Therefore, it can ensure that the hemming strip W stably and evenly forms the folding shape required by the reverse folding section W3. If this angle is too different from the right angle, the side portion 3121 and the ridge 3122 may not have the expected folding effect on the hemming strip W. For example, if the hemming tube 3 rotates around a fixed axis, the final angle between the delivery section W2 and the cloth feed channel 31 will be close to 45 degrees. At this time, the hemming strip W at the side portion 3121 may shrink and cause uneven folding.

[0056] It is not excluded that in other embodiments, different transmission ratios between the movable assembly 13 and the first rotating shaft O are set by a plurality of transmission devices. For example, in addition to realizing different designs of transmission ratios, a plurality of gear sets may also realize special requirements such as reversing transmission of the first rotating shaft O. Through similar designs, the coordination of the moving direction of the first rotating shaft O and the rotating direction of the hemming tube 3 can be ensured, and the two can be ensured to move in coordination along the preset direction.

[0057] The guide assembly 11 is to provide at least a translational component of the first rotation axis O moving toward the concave side of the initial position of the hemming tube 3 through the cooperation between the guide assembly 11 and the rolling assembly 12. The specific path of the guide assembly 11 and the cooperation mechanism do not need to be particularly limited. Figure 6 The technical solution that the guide assembly 11 has an arc-shaped path is provided, but it does not exclude the possibility of using a straight path or other curved paths. Figure 8 An embodiment of linear motion is shown.

[0058] Fig. 9 Schematic diagram of the structure of the hemming tube 3 of the present invention. Generally speaking, the technical solution of the present application can be realized by adopting the hemming tube structure in the prior art. Generally speaking, the resistance between the hemming strip W and the hemming tube 3 can overcome its retreat, but in order to ensure the occurrence of the retreat phenomenon and ensure its working stability, it is preferably necessary to design a reliable non-return mechanism. Fig. 9 The embodiment of such an edge wrapping tube 3 is shown in FIG. The edge wrapping tube 3 has a cloth feeding channel 31 for conveying the edge wrapping strip W and guiding the edge wrapping strip W to a preset cross section. A check piece 313 is arranged in the cloth feeding channel 31 to prevent the edge wrapping strip W from retreating in a direction opposite to the conveying direction.

[0059] In the process of retreating the hemming tube 3 from the extended hemming state to the retracted state in a compound motion mode in order to cut the hemming strip W, since the hemming strip W is still intact and can be driven forward or maintained by the feed dog 24, the hemming tube 3 is only equivalent to retreating relative to the hemming strip W, or the hemming strip W is considered to be accelerated relative to the hemming tube 3, and the non-return plate 313 basically does not hinder the advancement of the hemming strip W. When the hemming tube 3 is restored from the retracted state to the extended hemming state, it should be noted that the end of the hemming strip W has been cut off, so there is no possibility of fixing the end of the hemming strip W or pulling it forward. At this time, if the hemming tube 3 is reset to the hemming state under the compound motion, the hemming strip W will retreat relative to the cloth feeding channel 31. If there is no obstacle, the hemming strip W may retreat in the cloth feeding channel 31 during the resetting process of the hemming tube 3, causing the delivery segment W2 with good folding shape and direction that has been formed in the reverse wrapping channel 3123 in front of the cloth outlet 312 after cutting to retract into or behind the cloth feeding channel 31. On the one hand, since the hemming strip W is soft, this may cause the problem of unstable feeding caused by the difficulty of re-feeding consistent with the prior art. On the other hand, even if the feeding is relatively stable, the delivery segment W2 re-delivered from the cloth outlet 312 does not actually have the advantages of the original delivery segment W2. It has neither the expected folding shape that is the same as the reversed segment W3, nor the corresponding direction to the side of the reverse wrapping channel 3123. The check piece 313 can be as follows Fig. 9 What is shown is only an elastic sheet, one end of which is pressed against the edging strip W along the forward direction of the edging strip W. When the edging strip W tends to retreat, the edging strip W is further forced and prevented from moving because of the acute angle between the contact end of the elastic sheet and the retreat direction.

[0060] Generally speaking, in equipment such as hemming machines and sewing machines, a shearing mechanism 34 needs to be provided to match the hemming tube 3 to achieve a controlled shearing operation of the hemming strip W. In the embodiment of the present application, it is preferred that the shearing mechanism 34 and the hemming tube 3 are integrated into the same device as the hemming strip guide device 1. At this time, the position between the shearing mechanism 34 and the hemming tube 3 is relatively fixed after being adjusted appropriately, and is not affected by the specific installation position, nor does it cause the inconvenience of adjustment caused by being installed separately on the needle plate 23. The shearing mechanism 34 has a shearing component 341 that can be moved in a controlled manner. The shearing component 341 is placed on the concave side below the initial position of the hemming tube 3, and can generate a moving component in the direction away from and close to the hemming tube 3. The shearing component 341 contacts the hemming strip W and cuts it off during the process of moving toward the hemming tube 3. Fig.10In the embodiment, the cutting component 341 is preferably a hot cutter 342, that is, an electric heating wire arranged at the end of the cutting component 341, which melts the edge strip W when it contacts the edge strip W after heating. Generally, the cutting and feeding section W2 only requires the cutting mechanism 34 to move close to the edge tube 3 to contact the main cloth WW. In the specific technical solution, it is preferred to arrange the cutting mechanism 34 between the edge tube 3 and the presser foot 21, and make the cutting mechanism 34 move along the concave-convex direction of the edge tube 3 in the edge binding state, or at least there is a moving component in the concave-convex direction.

[0061] The technical solution of the present application also includes an edge binding machine 2 having an edge binding strip guiding device 1 . Fig.11 as well as Fig.12 Schematic diagram of the structure of the hemming machine 2. Fig.12 for Fig.11 An enlarged schematic diagram of the middle head part. The hemming strip guiding device 1 is arranged on the needle plate 23 of the hemming machine 2 and is located in the space behind the feed dog 24. The cloth outlet 312 of the hemming tube 3 extends forward to one side of the feed dog 24 during hemming. Optionally, a guide 25 is also arranged between the feed dog 24 and the cloth outlet 312 of the hemming tube 3 extending forward. The guide 25 is fixedly mounted on the needle plate 23 and has a guide surface protruding from the needle plate 23. When the cloth outlet 312 is away from the feed dog 24, the hemming strip W is cut off, and the cut hemming strip W that has been sewn with the main fabric WW still needs to be sewn to complete the finishing. At this time, although there is no support and guidance of the cloth outlet 312, the guide 25 can still guide the hemming strip W with the required folding shape to the edge of the main fabric WW for orderly and stable transportation.

[0062] Fig.13 This is a schematic diagram of the improved hemming strip guide device 1 of the present application. Note that in order to ensure that the folded section W3 is in a suitable position so that it can smoothly enter between the feed dog 24 and the presser foot 21 after wrapping the main fabric WW, the fabric outlet 312 should be located at the side of the feed dog 24 facing the main fabric WW inlet when the hemming state is in progress. Fig.11 , which means that the hemming tube 3 needs to be basically close to the surface of the needle plate 23, and even the lower side 3121 of its cloth outlet 312 may be lower than the surface of the needle plate 23, so that the reverse wrapping channel 3123 can face the feed inlet between the feed dog 24 and the presser foot 21. It can also be determined that for the hemming tube 3, in the process of the hemming strip W moving from the cloth inlet 311 to the cloth outlet 312, the width of the hemming strip W remains unchanged, but the cross-sectional shape changes. In the case of single-layer hemming, the original nearly straight shape changes to a U-shaped fold ( Figure 2 ), when double-layer hemming, it changes from the original straight line to double-layer folding ( Figure 3 ). In any case, for the hemming tube 3, the width of the cloth inlet 311 along the height direction will inevitably be significantly greater than the width of the cloth outlet 312, that is, Figure 1 As shown. When the hemming tube 3 rotates around the first rotation axis O, the lower end of the wider cloth inlet 311 may interfere with the surface of the needle plate 23. In order to avoid this problem, it is not enough for the hemming tube 3 to move only in the same horizontal plane when it moves from the hemming state to the retracting state. It is also necessary to move upward along its first rotation axis O, so that when retracting, the hemming tube 3 rises in the height direction to increase the distance between it and the needle plate 23, thereby avoiding collision between the cloth inlet 311 and the needle plate 23. In this embodiment, the height direction has a general meaning, that is, the direction in which the sewing machine is installed in a posture where the base is fixed at the bottom and the sewing needle is in the vertical direction, which is well known to those skilled in the art. When restarting a round of hemming operation, the hemming tube 3 completes the reverse process of the above process, that is, recovers from the exit state to the hemming state. In this process, the hemming tube 3 reverses around the first rotation axis O and the movable component 13 is restored. In addition, the hemming tube 3 simultaneously descends along the first rotation axis O to restore the height of the hemming state to face the feed port between the feed dog 24 and the sewing needle 22.

[0063] Fig.13 This is one implementation of the solution, and the movement of the hemming tube 3 in the height direction is achieved by the motion drive of the movable component 13. In this embodiment, the hemming strip guide device 1 has a support surface 132 fixedly arranged below the hemming tube 3, a part of the lower surface of the hemming tube 3 contacts the support surface 132, and an elastic component 133 is arranged between the hemming tube 3 and the movable component 13, and the elastic component 133 presses the hemming tube 3 against the surface of the support surface 132. Therefore, when the hemming tube 3 moves, the lower surface of the hemming tube 3 is always kept in contact with the support surface 132, that is, in the height direction, the hemming tube 3 is set in a floating manner. On this basis, the height of the support surface 13 on the projection path of the guide path of the guide component 11 in the vertical direction is set to be variable, and its height gradually transitions from a lower position when the hemming tube 3 is in the hemming state to a higher position when it is retracted. When the hemming tube 3 moves, its axis moves along the guide path of the guide assembly 11, forcing the hemming tube 3 to change its height accordingly under the limitation of the support surface 132, thereby avoiding interference when retracting, but at the same time ensuring that the height is lower during hemming than when retracting, and is in the correct position to align between the feed dog 24 and the presser foot 21.

[0064] Fig.14Another embodiment of the scheme is also based on the lifting movement of the hemming tube 3 driven by the movable component 13. A rotating component 134 linked with the rolling component 12 is arranged on the movable component 13. The rotating component 134 is arranged to rotate around the first rotating axis O and can slide along the first rotating axis O. When the movable component 13 is driven to move by the rolling component 12, the rotating component 134 rotates around the axis in linkage. The rotating component 134 is fixedly connected to the hemming tube 3. The movable component 13 also includes a fixed component 135 fixed relative to the swing arm 131. The fixed component 135 and the rotating component 134 form a spiral moving pair. The spiral guide groove 1341 of the fixed component 135 takes the first rotating axis O as the axis. The spiral guide groove 1341 can be arranged on the rotating component 134 or the fixed component 135. Therefore, when the rotating component 134 rotates around the axis in linkage, the hemming tube 3 moves accordingly. At the same time, under the side effect of the spiral movement, the rotating component 134 and the whole connected to the hemming tube 3 move up and down along the first rotating axis O.

[0065] Fig.15 For Fig.14 Or an improved embodiment based on other embodiments, a movable component 13 and a shearing mechanism 34 driven by a single power are provided. A multi-link mechanism 4 is provided between the edging tube 3 and the shearing mechanism 34 to realize the linkage between the two. For details, please refer to Fig.16 Schematic diagram after hiding the shielding structure, the multi-link mechanism 4 includes a connecting rod 41 and a rocking rod 42, wherein one end of the connecting rod 41 is rotatably connected to the eccentric position of the rolling assembly 12, and the other end is rotatably connected to one end of the rocking rod 42, and the other end of the rocking rod 42 slides and rotates between the shearing mechanism 34, specifically, it can be achieved by a motion-matching slide groove 421 set between the end of the rocking rod 42 and the shearing mechanism 34 and a slide shaft 343 sliding in the slide groove 421, and the slide shaft 343 and the slide groove 421 can be respectively set on the shearing mechanism 34 and the rocking rod 42, or vice versa. The middle position of the connection between the rocking rod 42 and the connecting rod 41 and the connection with the shearing mechanism 34 is rotatably connected to the fixed end 422. When the rolling assembly 12 rotates, the rocker 42 is driven to rotate around the fixed end 422 through the above-mentioned four-bar linkage, and the shearing mechanism 34 moves along a set path, such as the concave-convex direction of the hemming tube 3 in the hemming state, through the sliding rotation between the slide groove 421 and the slide shaft 343. In addition to being eccentrically connected to the rolling assembly 12, since the rolling assembly 12 is movably connected to the hemming tube 3, the rotating assembly 134 and other moving components, one end of the connecting rod 41 can also be flexibly rotatably connected to other moving components in the same moving mechanism such as the hemming tube 3, the rotating assembly 134, etc.

[0066] The above content only describes the preferred implementation mode of the present invention, and does not limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solution of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A hemming strip guiding device, comprising an hemming tube (3); The hemming tube (3) has a cloth feeding channel (31) for conveying the hemming strip (W), and a cloth inlet (311) and a cloth outlet (312) are formed at both ends of the cloth feeding channel (31); The cloth feeding channel (31) at the cloth outlet (312) has a U-shaped cross section, and the concave side of the hemming tube (3) is defined based on the direction of the inner concave surface of the U-shaped cross section, and the convex side of the hemming tube (3) is defined based on the direction of the outer convex surface of the U-shaped cross section; The hemming tube (3) forms a reverse-wrapping channel (3123) at the cloth outlet (312) and is opened facing the concave side; In the hemming state, the front is defined by the direction in which the material is discharged from the cloth outlet (312); the rear is defined by the opposite direction in which the material is discharged from the cloth outlet (312); It is characterized in that The hemming tube (3) has a first rotating shaft (O) behind the cloth outlet (312); When the hemming tube (3) exits the hemming state, the cloth outlet (312) rotates around the first rotating shaft (O) toward the convex side; and at the same time, the first rotating shaft (O) moves toward the concave side of the hemming tube (3) in the hemming state, so that when the hemming tube (3) rotates, there is at least a movement component toward the concave side of the hemming tube (3) in the hemming state, thereby ensuring that the hemming strip (W) always flows out along the reverse wrapping channel (3123) when the hemming tube (3) exits the hemming state.

2. The edge strip guiding device according to claim 1, characterized in that: The edge strip guiding device (1) comprises a fixed guiding component (11) and a movable component (13); The movable component (13) comprises an edge-binding tube (3) and a rolling component (12) rollingly arranged on the guide component (11); in the movable component (13), the rolling component (12) is transmission-connected to a first rotating shaft (O) of the edge-binding tube (3), and the first rotating shaft (O) is fixedly connected to the edge-binding tube (3); Alternatively, the edging tube (3) further includes a material stopping groove (3124) formed on the concave side and extending outward in the direction of the reverse-wrapping channel (3123), wherein the material stopping groove has a groove portion extending from the reverse-wrapping channel (3123) and raised edges on both sides of the groove portion, and the edges on both sides confine the edging strip within the material stopping groove (3124).

3. The edge strip guiding device according to claim 1, characterized in that: When exiting the hemming state, the hemming tube (3) moves upward along the axial direction of the first rotating shaft (O).

4. The edge strip guiding device according to claim 3, characterized in that: The hemming strip guiding device (1) comprises a fixed guiding component (11), a movable component (13), and a supporting surface (132) fixedly arranged below the hemming tube (3); The movable component (13) comprises an edge-binding tube (3) and a rolling component (12) rollingly arranged on the guide component (11); the rolling component (12) is drivingly connected to a first rotating shaft (O) of the edge-binding tube (3), and the edge-binding tube (3) and the first rotating shaft (O) are circumferentially fixed; The lower surface of the edging tube (3) is arranged in contact with the supporting surface (132), and an elastic component (133) is arranged between the edging tube (3) and the movable component (13), and the elastic component (133) presses the edging tube (3) against the surface of the supporting surface (132) along the axial direction of the first rotating shaft (O); the supporting surface (132) has a variable height so as to drive the edging tube (3) to move up and down when the edging tube slides on the supporting surface (132).

5. The edge strip guiding device according to claim 2, characterized in that: The movable component (13) is coaxially and fixedly connected to the first rotating shaft (O); Alternatively, when the hemming tube (3) exits the hemming state, the rolling component (12) rolls along an arc path on the guide component (11) so that the movable component (13) moves toward the concave side of the hemming tube (3) in the hemming state; Alternatively, when the hemming tube (3) exits the hemming state, the rolling component (12) rolls along a straight path on the guide component (11) so that the movable component (13) moves in a translational manner toward the concave side of the hemming tube (3) in the hemming state; Alternatively, the guide component (11) is a rack, the movable component (13) is a gear, and the gear meshes and rolls on the rack; Or, it also includes a shearing mechanism (34), the shearing mechanism (34) has a shearing component (341) that can be controlled to move; when the hemming tube (3) exits the hemming state, the shearing component (341) moves to contact the hemming strip (W) and cuts off the hemming strip (W); it also includes a multi-link mechanism (4), including a connecting rod (41) and a rocker (42), one end of the connecting rod (41) is rotatably connected to the eccentric position of the rolling assembly (12), and the other end is rotatably connected to one end of the rocker (42), and the other end of the rocker (42) slides and rotates between the shearing mechanism (34).

6. The edge strip guiding device according to claim 2, characterized in that: The movable component (13) is provided with a swing arm (131), one end of which is rotatably provided at a second rotating shaft (O2), and the rolling component (12) is rotatably provided on the swing arm (131) and rollingly cooperates with the guide component (11); the center of the circular arc path coincides with the second rotating shaft (O2).

7. The edge strip guiding device according to claim 2, characterized in that: The movable component (13) comprises a driving device (14) for driving the movable component (13) to roll.

8. The edge strip guiding device according to claim 7, characterized in that: The driving device (14) and the rolling assembly (12) are coaxially fixed; Alternatively, the driving device (14) is coaxially arranged with the second rotating shaft (O2), and the driving device (14) is transmission-connected with the rolling assembly (12).

9. The edge strip guiding device according to any one of claims 1 to 8, characterized in that: A non-return plate (313) is arranged in the cloth feeding channel (31) of the hemming tube (3), and the non-return plate (313) is used to prevent the hemming strip (W) from retreating in a direction opposite to the conveying direction.

10. The edge strip guiding device according to claim 9, characterized in that: The non-return sheet (313) is an elastic sheet, one end of which is pressed against the edge strip (W) along the conveying direction of the edge strip (W).

11. The edge strip guiding device according to any one of claims 1 to 8, characterized in that: It also includes a shearing mechanism (34), wherein the shearing mechanism (34) has a shearing component (341) capable of controlled movement; When the hemming tube (3) exits the hemming state, the shearing assembly (341) moves to contact the hemming strip (W) and cuts off the hemming strip (W).

12. A hemming machine, characterized in that: It comprises a edging strip guiding device as described in any one of claims 1-11.

13. The hemming machine according to claim 12, characterized in that: The needle plate (23) of the hemming machine (2) is provided with a reciprocating feed tooth (24), the hemming strip guide device (1) is arranged behind the feed tooth (24), and the hemming tube (3) extends forward to the feeding side of the feed tooth (24) in the hemming state.

14. The hemming machine according to claim 13, characterized in that: A guide (25) is fixedly arranged on the needle plate (23), and the guide (25) is located between the feed tooth (24) and the cloth outlet (312) of the forwardly extending hemming tube (3), and the guide (25) is used to guide the hemming strip (W) to enter the feed tooth (24).

Images