Multi-needle sewing machine

Abstract

The present invention addresses the problem of providing a multi-needle sewing machine equipped with an image-related device suitable for capturing or projecting an image during a sewing operation. As is well known, a multi-needle sewing machine comprises a needle bar case (10) that holds a plurality of needle bars, each comprising a sewing needle at the lower end thereof, so that the needle bars can move up and down, and that is capable of sliding laterally in order to select one of the needle bars. An image-related device (20) for capturing, projecting, or recognizing an image is disposed in front of the needle bar case (10) via a slide movement mechanism (30). The slide movement mechanism (30) is attached to the needle bar case (10), the image-related device (20) is mounted so as to be slidable laterally with respect to the needle bar case (10), and the image-related device is slid relative to the needle bar case. The image-related device (20) can be positioned above a needle drop position by being controlled by the slide movement mechanism (30) to slide laterally with respect to the needle bar case (10).

Description

Multi-needle sewing machine

[0001] The present invention relates to a multi-needle sewing machine that includes a needle bar case that is slidable laterally to hold multiple needle bars so that they can move up and down, and which allows sewing to be performed by selecting any of the needle bars to be used as the needle drop position, and further relates to an image-related device that can capture or project images.

[0002] In order to facilitate visual confirmation of the results of actual stitching performed on the workpiece (e.g., fabric) in a sewing machine, it is desirable to have a device that can capture images of the area near the needle drop position. In view of this, Patent Document 1 discloses a single-needle sewing machine that performs zigzag stitching or overlock stitching by alternately moving the needle drop position, and that has an image capturing device for capturing images of the area near the needle drop position installed in the sewing machine head. On the other hand, multi-needle sewing machines are also known that have a needle bar case that can slide laterally to hold multiple needle bars so that they can move up and down, and that select any of the needle bars to the needle drop position to perform sewing. In such a multi-needle sewing machine, the needle bar case is located on the front of the sewing machine head, and the sliding mechanism is located, for example, on the back side of the needle bar case, resulting in a complex structure, so the arrangement structure of the image capturing device in a single-needle sewing machine as shown in Patent Document 1 cannot be adapted to it.

[0003] In view of this, Patent Document 2 discloses an imaging device arrangement structure suitable for a multi-needle sewing machine in which the needle bar case is positioned on the front of the sewing machine head. In Patent Document 2, the imaging device is fixed to the side of the needle bar case, and the needle bar case is slid to switch the imaging device on the side so that it is positioned vertically above the needle drop position, thereby enabling the imaging device to image the stitch formed at the needle drop position. However, with such a structure, when the sliding position of the needle bar case is selected so that the imaging device is positioned vertically above the needle drop position, it is not possible to select any of the needle bars in the needle bar case as the needle drop position at the same time, so no sewing operation is performed. Therefore, there is a disadvantage in that it is not possible to image the vicinity of the needle drop position in real time while sewing is being performed by the up and down movement of the needle.

[0004] On the other hand, Patent Document 3 below discloses a structure in which an image projection device capable of projecting a still image corresponding to an arbitrary sewing pattern in the vicinity of the needle drop position is arranged in a multi-needle sewing machine having a needle bar case arranged in front of the sewing head. The arrangement structure fixes the base of a support member having a U-shaped bent shape to the sewing machine arm behind the needle bar case in a cantilever manner, and attaches an image projection device to the tip of the support member, so that the needle bar case is bypassed by the U-shaped support member and the image projection device is positioned in front of the needle bar case. As a result, the image projection device can be arranged at a fixed position facing the needle drop position regardless of the sliding movement of the needle bar case. However, the structure in which a large U-shaped support member that bypasses the needle bar case is cantilever-supported results in a configuration that bulges around the sewing head, so it is desirable to be improved. In addition, the large U-shaped support member that is cantilever-supported is likely to cause resonance vibration during the sewing operation by the up-and-down movement of the needle, which is not preferable.

[0005] Japanese Patent No. 3753445, Japanese Patent No. 4798242, Japanese Unexamined Patent Application Publication No. 2015-173876

[0006] The present invention has been made in view of the above points, and aims to provide a multi-needle sewing machine equipped with an image-related device suitable for photographing or projecting an image during a sewing operation.

[0007] The multi-needle sewing machine according to the present invention includes a sewing head, a plurality of needle bars having sewing needles at their lower ends and held so as to be vertically movable, a needle bar case slidable in the horizontal direction to select any one of the needle bars, an image-related device, and a slide movement mechanism attached to the needle bar case, the slide movement mechanism being configured to mount the image-related device slidably in the horizontal direction with respect to the needle bar case and slide the image-related device relatively with respect to the needle bar case. The image-related device is a device having at least one of the functions of image photographing, image projection, and image recognition.

[0008] According to this, the image-related device is mounted on the needle bar case via a sliding mechanism attached to the needle bar case, and is slidable relative to the needle bar case, so it can be positioned in any relative position to the needle bar case. Therefore, even when sewing is being performed with any needle bar selected in the needle bar case, the image-related device can be positioned above the needle drop position. Thus, it has the excellent effect of being able to image (or project or recognize) the workpiece near the needle drop position in real time while sewing is being performed by the up and down movement of the needle. Furthermore, since the image-related device is mounted on the needle bar case via a sliding mechanism, the overall configuration is compact. In addition, resonance vibrations and the like are less likely to occur during sewing by the up and down movement of the needle, so there is no risk of adversely affecting real-time image capture, image projection, or image recognition.

[0009] A front view of a multi-needle sewing machine according to one embodiment of the present invention. A perspective view mainly showing the needle bar case and image-related device in the multi-needle sewing machine according to the same embodiment. A schematic front view showing an example of the sliding operation of the needle bar case and image-related device in the multi-needle sewing machine according to the same embodiment.

[0010] Figure 1 is a front view of a multi-needle sewing machine according to one embodiment of the present invention. Figure 2 is a perspective view mainly showing the needle bar case 10 and the image-related device 20 of this multi-needle sewing machine. This multi-needle sewing machine is, as an example, a single-head sewing machine equipped with a single sewing head H, and the sewing head H is provided on the upper front of the sewing machine frame F that extends upward from the leg portion S. A needle bar case 10 equipped with multiple needle bars is slidably arranged laterally on the front of the sewing head H. A sliding mechanism 30 is attached to the needle bar case 10, and an image-related device 20 is mounted on the sliding mechanism 30 so as to be slid laterally relative to the needle bar case 10. The image-related device 20 is a device having at least one of the functions of image capture, image projection, and image recognition, and will be described as an image capture device (for example, a small video camera) as an example.

[0011] As shown in Figure 1, thread stand sections TS are provided extending to the left and right from appropriate locations on the sewing machine frame F, and multiple thread spools (not shown) are detachably installed on the thread stand sections TS. In addition, a thread introduction section TI is installed at a position extending upward from the sewing machine frame F. The thread introduction section TI includes components (omitted from the illustration for convenience) for introducing each color thread (upper thread) drawn upward from each thread spool of the thread stand section TS, and is configured to guide the introduced color threads to the sewing head H.

[0012] In the sewing machine frame F, a needle bar drive mechanism (not shown) is provided behind the sewing head H, which moves up and down in accordance with the rotation of the spindle motor (not shown). Below the sewing head H, a cylinder bed 1 is provided, extending forward from the sewing machine frame F. As is well known, a needle plate 2 with a needle pass-through hole is provided on the upper surface of the tip of the cylinder bed 1, and a bobbin case (not shown) that rotates in synchronization with the spindle motor is housed below the needle plate 2. Between the sewing head H and the cylinder bed 1, an embroidery hoop 3 is positioned so as to be movable in two dimensions in the X-Y direction. As is well known, the embroidery hoop 3 stretches and holds the workpiece (e.g., fabric), and is driven horizontally in two dimensions in the X-Y direction by a hoop drive device (not shown) provided on the side of the sewing machine frame F.

[0013] The sewing head H includes a needle bar case 10 that houses multiple needle bars (not shown) arranged side by side, each with a sewing needle attached to its lower end. The needle bar case 10 is slidable in the left-right direction (i.e., in the direction of the side-by-side arrangement of the needle bars) relative to the sewing machine frame F. When one needle bar is selected by sliding the needle bar case 10 and set or switched to a position (a vertically movable position) used for sewing, it is driven up and down by the needle bar drive mechanism, and the sewing needle attached to the selected needle bar moves up and down as it passes through the needle plate 2 of the cylinder bed 1.

[0014] An adjustment stand 11 is positioned on the upper part of the needle bar case 10, and the adjustment stand 11 slides and displaces integrally with the needle bar case 10 in the left-right direction (lateral direction). The adjustment stand 11 is equipped with a thread tensioner and thread break detection device that applies tension to the thread passing through each needle and adjusts that tension. In addition, the needle bar case 10 supports balances 12 corresponding to each needle bar so as to be able to swing up and down, and the tip of each balance 12 protrudes forward through vertical slits 13 formed in the front cover plate (not shown) of the needle bar case 10. Individual cover members 14 are provided on the front surface of the front cover plate corresponding to each balance 12, and these cover members 14 are removable.

[0015] Each upper thread, guided from the thread introduction section TI to the sewing head H, is set in the thread tension and thread break detection devices of the adjustment table 11, and then passed through the corresponding balance 12 before being passed through the sewing needle. When one needle bar selected by sliding the needle bar case 10 is driven up and down by the needle bar drive mechanism, the sewing needle attached to the selected needle bar moves up and down as it passes through the needle plate 2 of the cylinder bed 1. As is well known, a presser foot 15 is provided corresponding to each sewing needle, and the presser foot 15 moves up and down in synchronization with the up and down movement of the selected needle bar, pressing down the workpiece held in the embroidery hoop 3 near the needle drop position. Through the cooperation of the up and down moving sewing needle and the bobbin case provided in the cylinder bed 1, a main stitch operation is performed using the upper thread passed through the sewing needle and the bobbin thread drawn from the bobbin case, and embroidery stitching or other stitching is performed on the workpiece held in the embroidery hoop 3.

[0016] As shown in Figures 1 and 2, a sliding mechanism 30 for sliding an image-related device, i.e., an image capture device 20, is attached to the needle bar case 10 at a position below the cover member 14. The sliding mechanism 30 has, as an example, the following structure. A pair of left and right mounting brackets 31 are fixed to both the left and right sides of the needle bar case 10 and extend forward. Two upper and lower horizontal guide rails 32 are stretched and fixed between the two mounting brackets 31 at the front ends of the two mounting brackets 31. Furthermore, a loop-type transmission belt 33 is stretched between the two mounting brackets 31 via pulleys 34a and 34b in front of the horizontal guide rails 32. The right pulley 34a is rotatably mounted at the front end of the right mounting bracket 31 in a front view, and the left pulley 34b is rotatably mounted at the front end of the left mounting bracket 31 in a front view. The slider 35 is configured to slide-engage with the two upper and lower horizontal guide rails 32 and is connected to the transmission belt 33. An image acquisition device 20 is detachably attached to the lower surface of the slider 35, and the image acquisition device 20 is set to an appropriate tilt so that it can be directed towards the vicinity of the lower needle drop position. The slider 35 is configured so that this tilt can be adjusted by the operator's manual operation or the like.

[0017] A stepping motor 37, which is the drive source for the sliding mechanism 30, is located on the left side of the needle bar case 10. A loop-type transmission belt 38 is stretched between a pulley (not shown) provided on the rotation axis of the stepping motor 37 and a second pulley 34c provided coaxially with the left pulley 34b. As a result, the forward and reverse rotational motion of the stepping motor 37 is transmitted to the transmission belt 33 via the transmission belt 38, and the slider 35 (and image capture device 20) connected to the transmission belt 33 slides linearly in the left-right direction (lateral direction) while being guided by the horizontal guide rail 32.

[0018] The image capture device 20 (slider 35) is mounted on the needle bar case 10 via a sliding mechanism 30, so it slides laterally relative to the sewing head H (and cylinder bed 1) as the needle bar case 10 moves, but at the same time it can be controlled to slide relative to the needle bar case 10 in accordance with the forward or reverse rotation of the stepping motor 37. Typically, by controlling the image capture device 20 (slider 35) to slide relative to the needle bar case 10, the image capture device 20 can always be positioned above the needle drop position (cylinder bed 1), regardless of the current slide position (needle bar selection position) of the needle bar case 10.

[0019] As an example, the slide movement mechanism 30 is configured to move the image capture device 20 (slider 35) by the same amount as the amount the needle bar case 10 moves, in the opposite direction to the direction in which the needle bar case 10 moves, in accordance with the sliding of the needle bar case 10. For example, when the needle bar case 10 is slid 5 stitches to the right to switch the selected needle bar from the 8th stitch to the 3rd stitch, the image capture device 20 (slider 35) slides 5 stitches to the left. With this type of slide control, the image capture device 20 (slider 35) can always be positioned at the same position (for example, above the needle drop position (cylinder bed 1)) regardless of the sliding movement of the needle bar case 10, with simple control.

[0020] Figure 3 is a schematic front view showing an example of the sliding operation of the needle bar case 10 and the image acquisition device (image-related device) 20. Figure 3(a) shows the needle bar case 10 selected in the central neutral position. In this state, the image acquisition device 20 (slider 35) may be in any sliding position, but for convenience, it is assumed to be located above the needle drop position (opposite the cylinder bed 1) as shown in the figure.

[0021] When starting sewing from the state shown in Figure 3(a) by selecting the rightmost needle bar (sewing needle), the needle bar case 10 slides to the left (in the direction of arrow A) relative to the sewing head H in a front view, and as shown in Figure 3(b), the rightmost needle bar (sewing needle) is positioned above the needle drop position (opposite the cylinder bed 1). With the desired needle bar (sewing needle) thus selected, the sewing operation is performed as described above. In this case, simultaneously with the sliding movement of the needle bar case 10, or at an appropriate point before or after, the image capturing device 20 (slider 35) is slid to the right relative to the needle bar case 10 (in the direction of arrow B, i.e., opposite to the direction of movement A of the needle bar case 10) by the sliding movement mechanism 30, thereby positioning the image capturing device 20 above the needle drop position (opposite the cylinder bed 1). This allows the image capturing device 20 to capture still images or videos showing the sewing state of the workpiece near the needle drop position. Therefore, the image capture device 20 can capture images of the area near the needle drop position while sewing is in progress. Of course, it is not limited to during sewing; the sewing state on the workpiece can also be captured when the up-and-down movement of the sewing needle is temporarily paused (without cutting the thread), or the finished state of embroidery or other stitching on the workpiece can be captured when the sewing operation is complete. According to this embodiment, such captures during pauses or at the end of sewing can be performed quickly.

[0022] As is well known, when switching the needle bar (sewing needle) used for sewing, the needle bar case 10 is slid to select the desired needle bar (sewing needle). For example, when selecting the leftmost needle bar (sewing needle), the needle bar case 10 is slid to the right (in the direction of arrow C) relative to the sewing head H in a front view, so that the leftmost needle bar (sewing needle) is positioned above the needle drop position (opposite the cylinder bed 1), as shown in Figure 3(c). In this case as well, simultaneously with the sliding movement of the needle bar case 10, or at an appropriate point before or after, the image capturing device 20 (slider 35) can be slid to the left relative to the needle bar case 10 (in the direction of arrow D, i.e., opposite to the direction of movement C of the needle bar case 10) by the sliding movement mechanism 30, thereby positioning the image capturing device 20 above the needle drop position (opposite the cylinder bed 1). In this way, regardless of which needle bar (sewing needle) is selected for sewing, the image capture device 20 can continuously capture images of the area near the needle drop position during the sewing process, and furthermore, as described above, images can be quickly captured when the sewing is paused or completed.

[0023] As shown in Figure 1, a display device 40 is positioned at an appropriate location, such as to the right of the sewing head H, and can display videos or still images captured by the image capture device 20 in real time on the display device 40. The sewing machine operator can check the sewing status in real time while sewing by viewing the video or still image of the area near the needle drop position displayed on the display device 40.

[0024] The video or still image information captured by the image capture device 20 can be displayed in real time using the display device 40, or it can be stored in the internal memory of the multi-needle sewing machine or in an appropriate external memory. The multi-needle sewing machine may also be equipped with a communication interface for communicating information or data with the outside, and the video or still image information captured by the image capture device 20 can be transmitted to the outside via this communication interface.

[0025] The image-related device 20 attached to the slide movement mechanism 30 is not limited to the image capture device described above, but may also be an image projection device. In that case, the electronic control device (microprocessor and memory, etc.) equipped in the multi-needle sewing machine is configured to generate appropriate image information, and the image-related device 20, which consists of an image projection device, projects an image based on the generated image information onto the workpiece (fabric) near the needle drop position. This allows the operator to visually confirm the image projected onto the workpiece (fabric), thereby facilitating the sewing process. For example, by projecting an image showing the desired embroidery pattern while performing embroidery, the progress of the embroidery pattern on the workpiece (fabric) can be compared and confirmed in real time. It is also advisable to display the image on the display device 40 in order to select or confirm the image to be projected. The screen of the display device 40 may be a touch panel, in which case it can also be used as a user interface (input device).

[0026] The image-related device 20 attached to the slider 35 may be standardized to be detachable from either an image capture device or an image projection device, allowing it to be switched between the two as needed. Alternatively, both an image capture device and an image projection device may be attached to the slider 35 as the image-related device 20. Furthermore, the image capture device used as the image-related device 20 is not limited to one with normal video camera functions, but may also be an image recognition device (or reading device) specialized in other appropriate special functions. An image recognition device specialized in special functions is, for example, a device that recognizes two-dimensional codes or barcodes and reads them as data. As an example, an embodiment may be adopted in which special information such as two-dimensional codes or barcodes is attached to the embroidery hoop 3 or the workpiece, and the image recognition device (image-related device 20) can recognize and read it as appropriate at the start of sewing, during sewing, or at the end of sewing. The recognized or read image or information based on the image can be displayed on the display device 40.

[0027] Needless to say, various controls in this multi-needle sewing machine, such as the slide control of the needle bar case 10 and the slide control of the image-related device 20 (slide movement mechanism 30) as described above, can be performed by an electronic control device provided in the multi-needle sewing machine. In this case, the electronic control device incorporates a computer program and other programs for executing the slide control method of the image-related device 20 (slide movement mechanism 30) as described above, and is configured to be executed by a microprocessor.

[0028] The present invention is not limited to single-head sewing machines as described in the above embodiment, but can also be applied to multi-head sewing machines equipped with multiple sewing heads.

Claims

1. A multi-needle sewing machine comprising: a sewing head; a needle bar case that holds multiple needle bars, each having a sewing needle at its lower end, so as to be able to move up and down, and is slidable laterally for selecting any of the needle bars; an image-related device; and a sliding mechanism attached to the needle bar case, wherein the image-related device is mounted so as to be able to slide laterally relative to the needle bar case, and the sliding mechanism slides the image-related device relative to the needle bar case.

2. The multi-needle sewing machine according to claim 1, wherein the image-related device can be positioned above the needle drop position in the sewing head by sliding control relative to the needle bar case by the sliding movement mechanism.

3. The multi-needle sewing machine according to claim 1, wherein the sliding mechanism moves the image-related device in the opposite direction to the direction in which the needle bar case moves by the same amount as the amount of movement of the needle bar case, in accordance with the sliding of the needle bar case.

4. The multi-needle sewing machine according to any one of claims 1 to 3, wherein the image-related device is a device having at least one of the functions of image capture, image projection, and image recognition.

5. The multi-needle sewing machine according to claim 4, wherein the image-related device is an image capturing device capable of capturing an image of the vicinity of the needle drop position.

6. The multi-needle sewing machine according to claim 5, wherein the image capturing device generates video and / or still image information of the captured image.

7. The multi-needle sewing machine according to claim 4, wherein the image-related device is an image projection device capable of projecting an image near the needle drop position.

8. The multi-needle sewing machine according to claim 4, further comprising a display device capable of displaying an image captured, projected, or recognized by the image-related device.

Images