Tatami mat sewing device

Abstract

To provide a tatami mat sewing device capable of easily adjusting position of a sewing needle with respect to a tatami mat to a proper position in a height direction and a depth direction even if a thickness of the tatami mat changes.SOLUTION: A tatami mat sewing device sews a tatami mat edge to lateral sides of a tatami mat by performing backstitching or frame stitching on the lateral sides of the tatami mat. The tatami mat sewing device comprises: a sewing mechanism that is mounted with a sewing needle having a hole through which a needle thread is passed, and performs sewing operation to the tatami mat by oscillating the sewing needle; and a lifting mechanism to move a position of the sewing needle up and down. The lifting mechanism has a lifting mechanism motor to drive the lifting mechanism. The sewing mechanism has a sewing machine pivot as a pivot for the sewing mechanism, a sewing needle drive shaft to derive the sewing needle, and a sewing mechanism motor to drive the sewing needle. The height direction and depth direction of sewing by the sewing needle can be simultaneously adjusted based on rotation of the lifting mechanism motor.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a tatami sewing device for sewing a tatami edge to a side edge of a tatami, and more particularly to a tatami sewing device for performing overcasting on a side edge of a tatami and sewing a tatami edge to a side edge of a tatami.

Background Art

[0002] Conventionally, in the manufacturing process of tatami, a hemming process of sewing a tatami surface to the side surface of the short side of the tatami and an overcasting process of sewing a tatami edge to the side surface of the long side of the tatami have been carried out.

[0003] In the production of tatami, depending on the place where the tatami is laid, tatami with different thicknesses, such as thick tatami and thin tatami, are used. Therefore, when manufacturing tatami, it is necessary to change the height position of the sewing needle for sewing the tatami according to the thickness of the tatami.

[0004] Patent Document 1 discloses a tatami sewing device that changes the height position of the sewing needle for sewing the tatami by rotating the sewing machine arm around the sewing machine arm shaft in order to correspond to the thickness of the tatami. This tatami sewing device rotates the sewing needle swing shaft through the rotation of the crank, via the crank rod and the needle arm lever, to reciprocate the needle arm and the sewing needle.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, simply changing the height position of the sewing needle for tatami mats does not result in a constant sewing depth, and the strength of the double stitch becomes unstable. Specifically, when using the sewing needle position used for thick tatami mats without changing it for thin tatami mats, the sewing needle will pierce from the flat surface instead of the side of the tatami mat (see Fig. 10).

[0007] Therefore, as in the tatami sewing device of Patent Document 1, when the height position of the sewing needle is simply lowered according to the thin tatami mat, there are problems such as insufficient sewing depth (depth in the lateral direction of the tatami mat) and inability to fix the edge cloth, and the distance for sewing the thread becomes short, resulting in poor tightening of the thread and inferior strength of the double stitch (see Fig. 11).

[0008] In addition, if the needle penetration position (sewing height) is too high above the tatami mat, the tatami surface may bulge due to the needle holes and the appearance may deteriorate. When sewing with a wide edge width at the tatami edge, if the needle penetration position (sewing height) is too low, the edge cannot be sewn (see Fig. 12).

[0009] In conventional tatami sewing devices, in order to avoid such inappropriate sewing positions, it is necessary for the operator to manually adjust the sewing depth after adjusting the height position of the sewing needle to achieve an appropriate sewing position, which requires complicated operations.

[0010] Also, as in the tatami sewing device of Patent Document 1, since the sewing machine arm shaft serving as the sewing machine turning shaft and the crank shaft serving as the needle drive shaft are used as separate parts, the structure becomes complicated, the number of parts increases, the size of the device itself becomes large, and the cost also increases.

[0011] In view of such a situation, an object of the present invention is to provide a tatami sewing device that can perform a good-looking double stitch at an appropriate sewing position according to the thickness of the tatami mat without the operator having to adjust the sewing height and sewing depth according to the thickness of the tatami mat. Another object is to provide a tatami sewing device that can reduce the number of parts, suppress the size of the device itself, and reduce the cost.

Means for Solving the Problems

[0012] The folding and sewing device according to one aspect of the present invention is a folding and sewing device for performing overcasting or edge sewing on the side edge of a fold and sewing a folded edge on the side edge of the fold, comprising a sewing needle equipped with a hole through which an upper thread is inserted, and a sewing mechanism for performing a sewing operation on the fold by swinging the sewing needle, and a lifting mechanism for lifting and lowering the position of the sewing needle. The lifting mechanism has a motor for the lifting mechanism for driving the lifting mechanism, and the sewing mechanism has a sewing machine turning shaft serving as a turning shaft of the sewing mechanism, a sewing needle drive shaft for driving the sewing needle, and a motor for the sewing mechanism for driving the sewing needle. Based on the rotation of the motor for the lifting mechanism, the height direction and the depth direction of the sewing of the sewing needle can be adjusted simultaneously.

[0013] By configuring in this way, since the position of the sewing needle can be adjusted in the appropriate height direction and depth direction, even if the thickness of the fold changes, overcasting with good finish can be performed. In addition, complicated manual work of the operator is not required, and the work efficiency can be improved.

[0014] Further, this folding and sewing device is characterized in that the sewing machine turning shaft of the sewing mechanism and the sewing needle drive shaft are the same shaft.

[0015] By configuring in this way, since the sewing machine turning shaft and the sewing needle drive shaft are configured on the same shaft, reduction in the number of parts and simplification of the structure can be achieved, and space saving is possible.

[0016] Further, this folding and sewing device is such that the sewing mechanism has a sewing needle swing shaft on which the sewing needle swings, and a connecting member and a cam connecting the sewing needle drive shaft and the swing shaft.

[0017] By configuring in this way, the sewing needle can be driven to swing through the sewing needle drive shaft, the connecting member, the cam, and the swing shaft by the above-described motor for the sewing mechanism.

[0018] In addition, this folding sewing device is characterized in that the sewing mechanism includes a bobbin that accommodates a bobbin wound with the lower thread, and has a shuttle that is rotationally driven in conjunction with the driving of the sewing needle, and the shuttle rotation drive shaft that rotationally drives the shuttle is the same shaft as the sewing needle drive shaft.

[0019] With this configuration, it is possible to simultaneously drive the sewing needle and rotate the shuttle with one motor, and by configuring the shuttle rotation drive shaft and the sewing needle drive shaft to be the same shaft, the synchronization of the operations becomes easy and the device can be made more space-saving.

[0020] Further, this folding sewing device is characterized in that the shuttle rotation drive shaft is the same shaft as the sewing machine swivel shaft and the sewing needle drive shaft.

[0021] With this configuration, since the shuttle rotation drive shaft, the sewing machine swivel shaft, and the sewing needle drive shaft are coaxial, the device can be made even more space-saving.

[0022] Furthermore, this folding sewing device is characterized in that the sewing mechanism includes a balance for pulling up the upper thread, the balance is arranged at a position close to the end side opposite to the end side where the sewing needle is located, and the balance drive shaft for driving the balance is the same shaft as the sewing machine swivel shaft.

[0023] With this configuration, by configuring the drive shaft of the balance to be the same shaft as the sewing machine swivel shaft, the device can be made space-saving.

[0024] Moreover, this folding sewing device is characterized in that the balance drive shaft is the same shaft as the sewing machine swivel shaft and the sewing needle drive shaft.

[0025] With this configuration, by configuring the balance drive shaft, the sewing machine swivel shaft, and the sewing needle drive shaft to be the same shaft, the device can be made even more space-saving.

[0026] Further, this tatami sewing device accommodates a bobbin wound with a lower thread, and has a cutter that is rotationally driven in conjunction with the drive of the sewing needle. A cutter rotation drive shaft for rotationally driving the cutter is characterized in that the sewing machine turning shaft, the sewing needle drive shaft, and the balance drive shaft are on the same axis.

[0027] By configuring in this way, since the four shafts of the sewing machine turning shaft, the sewing needle drive shaft, the cutter rotation drive shaft, and the balance drive shaft are on the same axis, the entire device can be made very space-saving.

[0028] Also, in this tatami sewing device, a motor for the sewing mechanism is disposed at an end of the sewing mechanism, and the motor for the sewing mechanism is connected to the sewing machine turning shaft by a sprocket or a belt. The arrangement of the motor for the sewing mechanism, the sewing machine turning shaft, the sewing needle drive shaft, and the sewing needle swing shaft is fixed, and the motor for the sewing mechanism also moves up and down according to the elevation of the position of the sewing needle.

[0029] By configuring in this way, the arrangement of the motor for the sewing mechanism, the sewing machine turning shaft, the sewing needle drive shaft, and the sewing needle swing shaft is fixed, and the motor for the sewing mechanism moves up and down according to the elevation of the sewing needle. Therefore, even if the sewing machine turning shaft and the sewing needle drive shaft are on the same axis, since the motor for the sewing mechanism moves in conjunction with the entire sewing machine, it is possible to prevent the sewing needle from moving.

[0030] That is, when the motor is fixed, the rotation of the sprocket or belt causes the sewing needle to move. However, since the motor is not fixed and moves up and down in synchronization, in one operation, the height and depth can be changed simultaneously with respect to the thickness of the tatami, and since the sewing needle does not move, accurate adjustment is possible when adjusting the height and depth of the sewing needle.

[0031] Also, this tatami sewing device is characterized in that the sewing machine turning shaft is provided near the center of the sewing mechanism.

[0032] By configuring it in this way, by adjusting the appropriate sewing height according to the thickness of the tatami, the sewing depth can also be adjusted. Therefore, it becomes unnecessary for the operator to perform a two-step operation of depth adjustment in addition to height adjustment, and the work efficiency of the operator can be improved. As a result, even when the thickness of the tatami changes, it is possible to perform a good-quality double stitch with appropriate sewing height and sewing depth.

[0033] Further, in this tatami sewing device, the sewing needle is arranged on one end side of the sewing mechanism with respect to the sewing machine turning shaft, and the balance is arranged on the other end side of the sewing mechanism with respect to the sewing machine turning shaft.

[0034] By configuring it in this way, even when the sewing device is moved around the sewing machine turning shaft according to the thickness of the tatami, the positional relationship between the balance and the sewing needle is fixed, and since the sewing machine turning shaft, the sewing needle drive shaft, and the balance drive shaft are on the same axis, even when the thickness of the tatami changes, the balance and the sewing needle always operate in synchronization, enabling stable sewing.

[0035] Further, in this tatami sewing device, the motor for the lifting mechanism is a servo motor.

[0036] By configuring it in this way, it can be reciprocally driven accurately and quickly by controlling the servo motor.

[0037] Further, this tatami sewing device further includes tatami thickness measuring means capable of measuring the thickness of the tatami. The tatami thickness measuring means has a tatami presser that moves up and down and a lifting means for lifting the tatami presser, and measures the thickness of the tatami using the moving distance of the tatami presser.

[0038] By configuring it in this way, the thickness of the tatami can be measured accurately and easily, so it is possible to perform a good-quality double stitch with appropriate sewing height and sewing depth.

[0039] Further, this tatami sewing device is configured such that the tatami thickness measuring means measures the tatami thickness by subtracting, from a reference distance, the moving distance of the tatami presser until it abuts against the tatami surface and stops, where the reference distance is the distance between the position of the bottom surface of the tatami and the upper limit position of the tatami presser in the standby state.

[0040] By configuring it in this way, when actually measuring the tatami thickness, although it is necessary to separately add an independent measuring means, it is suitable to measure the tatami thickness using the reference distance and the moving distance of the tatami presser because there will be no interference during sewing.

[0041] Also, this tatami sewing device is characterized in that the elevating means includes a driving means and a link mechanism connected to the presser, and an encoder attached to the link mechanism, and the tatami thickness is measured by converting the rotation amount of the link constituting the link mechanism by the encoder into a distance in the height direction to obtain the moving distance of the tatami presser.

[0042] By configuring it in this way, it becomes possible to measure the moving distance and the tatami thickness simply by attaching an encoder to the link mechanism, which is suitable without interfering with sewing.

[0043] Further, this tatami sewing device is characterized by comprising control means for adjusting the sewing height direction and depth direction of the sewing needle by controlling the elevator mechanism motor based on the tatami thickness measured by the tatami thickness measuring means.

[0044] By configuring it in this way, it is possible to surely sew according to the tatami thickness, and prevent the sewing needle from interfering with other parts and breaking, or being in a position where sewing is impossible, or the stitches being dirty and resulting in a poor finish.

[0045] Further, this tatami sewing device is characterized by comprising a determination means for determining whether or not the positions of the sewing needle in the height direction and the depth direction of sewing are within the range of an appropriate sewing position based on the thickness of the tatami measured by the tatami thickness measuring means, and a failure prevention means for preventing failure when the positions are not within the range of an appropriate sewing position.

[0046] Here, the failure prevention means includes, for example, stopping sewing (not starting sewing), notification by a warning lamp, etc. By configuring in this way, in the unlikely event that the sewing needle is not within the allowable range in the height direction and the depth direction of sewing, it is possible to prevent the sewing needle from interfering with other parts and breaking, or prevent a sewing machine failure due to being unable to sew the tatami edge.

[0047] In addition, by providing this failure prevention means, when it is desired to adjust the sewing height and sewing depth beyond the initial range set for a general tatami, or in the case of a special tatami different from the thickness and size of a general tatami, it is possible to not start sewing or give a warning when the positions of the sewing needle in the height direction and the depth direction of sewing are not within the allowable range. Thereby, in the case of a special tatami or the like, it is possible to prevent interference, breakage of the sewing needle, and sewing machine failure.

Advantages of the Invention

[0048] According to the present invention, even when the thickness of the tatami changes, it is possible to perform a good-quality double sewing by adjusting to appropriate positions in the height direction and the depth direction of sewing the sewing needle with respect to the tatami. Further, the complicated labor of the operator is unnecessary, and it becomes possible to improve the work efficiency.

[0049] In addition, according to another aspect, the number of parts can be reduced, and it is possible to reduce costs and simplify the assembly work.

[0050] In another aspect, by providing a control means for adjusting the sewing height and depth directions of the stack thickness measuring means and the sewing needle, it is possible to surely sew according to the thickness of the stack, preventing the sewing needle from interfering with other parts and breaking, or being in a position where sewing is impossible, or the stitches from becoming dirty and finished.

Brief Description of the Drawings

[0051]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Modes for Carrying Out the Invention

[0052] Hereinafter, a folding sewing device according to an embodiment of the present invention will be described in detail. Note that the present invention is not limited by this embodiment. Further, the constituent elements in the following embodiments include those that can be replaced by those skilled in the art and are easy to replace, or those that are substantially the same. Furthermore, the configurations described below can be combined as appropriate. Also, various omissions, substitutions, or changes in the configuration can be made without departing from the gist of the present invention.

[0053] (1. Overall Configuration of the Folding Sewing Device) FIG. 1 is a plan view showing a schematic configuration of the folding sewing device of the present embodiment, and FIG. 2 is a side view showing the schematic configuration of the sewing device.

[0054] In the folding sewing device of the present embodiment, the side edge 110 of the stack 100 means the longitudinal side of the stack 100 when the stack 100 is for one stack, and the side perpendicular or substantially perpendicular to the side of the frame when it is for a half stack. Also, the left - right direction (longitudinal direction of the stack) in FIG. 1 is defined as the A direction, the up - down direction (short - hand direction of the stack) is defined as the B direction, and the up - down direction (thickness direction of the stack) in FIG. 2 is defined as the C direction.

[0055] As shown in FIGS. 1 and 2, the folding sewing device 1 of the present embodiment is a device for sewing the folding edge, and mainly includes a sewing machine body 10, a mounting table 11 for mounting the stack 100, and a frame 12. Also, on the mounting table 11, a central base extending in the A direction in FIG. 1 and a plurality of rollers 11A are respectively attached to the left and right of the central base at a predetermined interval in the A direction. Thereby, the mounted stack 100 can be conveyed along the A direction.

[0056] Further, the sewing machine bodies 10 are respectively arranged on both sides of the mounting table 11 in the B direction perpendicular to the A direction. Then, with the A direction in FIG. 1 as the longitudinal direction of the stack 100, while feeding the stack 100 in the A direction with the stack 100 mounted on the mounting table 11, the sewing machine body 10 performs back - stitching on the side edge 110 of the stack 100 to sew the folding edge to the side edge 110 of the stack 100.

[0057] (2. Configuration of the Sewing Machine Body) Next, the sewing machine main body 10, which is the main configuration of the folding and sewing device of the present embodiment, will be described. FIG. 3 is a front view of the sewing machine main body portion of the sewing device of the present embodiment, FIG. 4 is a side view of the sewing machine main body portion with the sewing needle in the upper position, FIG. 5 is a side view of the sewing machine main body portion with the sewing needle in the lower position, FIG. 6 is a plan view of the sewing machine main body portion, and FIG. 7 is an explanatory view for explaining the position adjustment of the sewing needle in the sewing height direction and depth direction of the sewing machine main body portion.

[0058] As shown in FIGS. 3 to 6, the sewing machine main body 10 mainly includes a sewing mechanism 20, a lifting mechanism 30, and a motor 40 for the lifting mechanism.

[0059] The sewing mechanism 20 is a mechanism for performing an operation of sewing the folded edge with respect to the side edge 110 of the stack 100. The sewing mechanism 20 performs a sewing operation by swinging while receiving a driving force from the sewing mechanism motor 25.

[0060] The sewing mechanism 20 includes a sewing machine arm 21, a needle arm 22, a cam 23, a connecting member 24, a sewing mechanism motor 25, and a presser foot 26.

[0061] The sewing machine arm 21 is provided so as to be swingable about a sewing machine swing axis 211 that serves as a swing axis of the sewing mechanism 20. By swinging the sewing machine arm 21, the sewing height position and depth position of the sewing needle 112 with respect to the stack 100 are changed.

[0062] The handle shaft 51 is provided in a state of passing through the sewing machine arm 21, and a circular handle 50 is attached to one end. The handle 50 is provided for cases where it is easier to control by rotating the handle 50 manually rather than by a motor, such as when the handle 50 stops due to an overload or the like, such as when a foreign object is bitten during the sewing operation, and it is necessary to rotate the handle 50 in either the forward or reverse direction to remove the foreign object and move the needle presser foot. By rotating the handle shaft 51, the sewing machine arm 21 is integrally rotated. That is, the handle shaft 51 serves as the sewing machine swing axis 211.

[0063] The sewing machine turning shaft 211 is provided near the center of the sewing mechanism 20. As a result, in one operation, the sewing height is adjusted according to the thickness of the stack, and the sewing depth is also adjusted. That is, as shown in FIGS. 7(a) and 7(b), the position of the sewing needle swing shaft 221, which is the rotation center of the needle arm 22 to which the arc-shaped sewing needle 112 is attached, can be adjusted from the sewing position (X1, Y1) of the thick stack to the sewing position (X2, Y2) of the thin stack. Therefore, the two-step position adjustment for moving the sewing machine by δX and δY is not required.

[0064] The needle arm 22 is provided at the upper part of the sewing machine arm 21 so as to be swingable about the sewing needle swing shaft 221. An arc-shaped sewing needle 112 is attached to the tip of the needle arm 22. A sewing thread called the upper thread is passed through the sewing needle 112.

[0065] The cam 23 rotates by receiving power from the sewing mechanism motor 25 and is for swinging the needle arm 22. Further, since the outer periphery of the cam 23 is non-uniform, the guide roller 71 rotates along the outer periphery of the cam 23, and the balance 70 physically determines the amount of pulling the thread. The rotational force of the sewing mechanism motor 25 is transmitted to the sprocket 52 and the handle shaft 51 via the sprocket 252 and the chain 60, and is transmitted to the cam 23 by the rotation of the handle shaft 51.

[0066] One end of the connecting member 24 is rotatably connected to the cam 23, and the other end is rotatably connected to the sewing needle swing shaft 221. The connecting member 24 swings the needle arm 22 about the sewing needle swing shaft 221 by the rotation of the cam 23.

[0067] The rotation of the handle shaft 51 is transmitted to the sewing needle swing shaft 221 via the connecting member 24, so that the sewing needle swing shaft 221 rotates and the needle arm 22 swings. That is, the handle shaft 51 serves as the sewing needle drive shaft 113.

[0068] Therefore, the sewing machine turning shaft 211 and the sewing needle drive shaft 113 are the same shaft. As a result, the number of parts can be reduced and the structure can be simplified.

[0069] The sewing mechanism motor 25 is disposed at the end of the sewing mechanism 20. The arrangement of the sewing mechanism motor 25, the sewing machine turning shaft 211, the sewing needle drive shaft 113, and the sewing needle swing shaft 221 is fixed, and the sewing mechanism motor 25 is lifted and lowered according to the position of the sewing needle 112. Thereby, even if the sewing machine turning shaft 211 and the sewing needle drive shaft 113 are on the same axis, since the sewing mechanism motor 25 moves in conjunction with the entire sewing machine, it is possible to prevent the sewing needle 112 from moving.

[0070] A chain 60 is hung between a sprocket 252 attached to the rotating shaft 251 of the sewing mechanism motor 25 and a sprocket 52 attached to the handle shaft 51. The rotation of the sewing mechanism motor 25 is transmitted to the handle shaft 51 via the chain 60.

[0071] The bobbin case 26 houses a bobbin wound with the lower thread for sewing and is rotationally driven in conjunction with the drive of the sewing needle 112. Further, the bobbin case 26 is attached to the tip of the sewing machine arm 21, rotates synchronously with the needle arm 22 to perform a sewing operation, and as the sewing machine arm 21 swings with the sewing machine turning shaft 211 as a fulcrum, the bobbin case 26 and the needle arm 22 move up and down, changing the height position and depth position of the sewing of the sewing needle 112.

[0072] The bobbin case 26 is attached to the tip of the sewing machine arm 21, and since the central axes of the bobbin case 26 and the sewing mechanism motor 25 are the sewing machine turning shaft 211, the operation of the sewing mechanism 20 becomes stable.

[0073] The rotational force of the sewing mechanism motor 25 is transmitted to the handle shaft 51 via the sprocket 252 and the chain 60. Due to the rotation of the handle shaft 51, the bevel gear 263 attached to the handle shaft 51 rotates, power is transmitted to the bobbin case shaft 261, and is transmitted to the bobbin case 26 via the bobbin case shaft 261. That is, the handle shaft 51 serves as the bobbin case rotation drive shaft 262, and the bobbin case rotation drive shaft 262 is on the same axis as the sewing machine turning shaft 211 and the sewing needle drive shaft 113.

[0074] The elevating mechanism 30 is driven based on the rotation of the motor 40 for the elevating mechanism. As shown in FIGS. 4 and 5, the elevating mechanism 30 applies a moving force in the vertical direction (C direction) to the sewing mechanism 20 by the rotation of the motor 40 for the elevating mechanism, and swings the sewing mechanism 20, thereby changing the positions of the sewing needle 112 with respect to the tatami mat 100 in the height direction and the depth direction of sewing. Note that FIG. 4 shows the state of moving upward, and FIG. 5 shows the state of moving downward.

[0075] In addition, in the present embodiment, as an example, the elevating mechanism 30 can move within the range of sewing height from 7 mm to 38 mm, and is configured such that the sewing depth is 30 mm when the sewing height is 7 mm, and the sewing depth is 45 mm or more when the sewing height is 38 mm. By configuring in this way, it is possible to firmly perform double stitching or the like on tatami mats of various thicknesses from thin tatami mats to thick tatami mats. Note that the moving range with respect to the above-described sewing height and sewing depth is an example, and is not limited thereto, and it is also possible to configure it within the range of sewing height from 5 mm to 40 mm, the sewing depth is 20 mm or more when the sewing height is 5 mm, and the sewing depth is 45 mm or more when the sewing height is 40 mm.

[0076] Since the motor 40 for the elevating mechanism is configured by a servo motor capable of feedback control, it can be driven accurately and quickly.

[0077] The servo motor may be various servo motors capable of feedback control, such as a DC servo motor, an AC servo motor, and a pulse motor provided with encoder means capable of outputting a rotational phase angle signal.

[0078] The elevating mechanism 30 is composed of a plurality of links. Specifically, the base end portion of the first link 31 is connected so as to rotate integrally with the motor shaft 41 for the elevating mechanism. One end portion of the second link 32 is rotatably connected to one end portion of the first link 31, and the other end portion of the second link 32 is rotatably connected to one end portion of the third link 33.

[0079] The other end of the third link 33 is connected to the sewing machine arm 21. The third link 33 is connected near the sewing needle swing axis 221 of the sewing machine arm 21.

[0080] The balance 70 moves the upper thread supplied from the thread supply source up and down to the sewing needle 112. The balance 70 moves up and down during sewing to pull up the upper thread. It becomes possible to sew by passing through the needle hole of the sewing needle 112. The balance 70 is arranged at a position close to the end side opposite to the end side where the sewing needle 112 is located, and the balance drive shaft 701 for driving the balance 70 is on the same axis as the sewing machine turning axis 211. That is, the balance drive shaft 701 is on the same axis as the sewing machine turning axis 211 and the sewing needle drive shaft 113.

[0081] Also, FIG. 8 is a side view showing the configuration of the stack thickness measuring means of the present embodiment, and FIG. 9 is a front view showing the configuration of the stack thickness measuring means. As shown in FIGS. 8 and 9, the stack thickness measuring means 80 includes a stack presser 81, and the stack presser 81 moves up and down to press the upper surface of the stack 100 to fix the stack 100. Note that the stack presser 81 is configured to be able to move up and down between the position during the sewing operation shown by the solid line in FIGS. 4 and 5 and the retracted / standby state position shown by the dotted line.

[0082] Also, the stack thickness measuring means 80 mainly includes a stack presser 81, a link mechanism 82, and an air cylinder 83. By the expansion and contraction of the air cylinder 83, the stack presser 81 moves up and down while making a circular motion via the link mechanism 82. An encoder 84 is attached to the link mechanism 82. The encoder 84 is for converting the rotation amount of the link of the link mechanism 82 into a distance in the height direction. Note that the air cylinder 83 is an example of the present embodiment, and an electric cylinder or the like may be used.

[0083] The stack presser 81 mainly includes a support member 81A, four pulleys 81B rotatably attached thereto, and a belt 81C. The pulleys 81B are attached to the left and right sides with a predetermined interval in the front-rear direction, and the belt 81C is attached to a pair of pulleys 81B on each of the left and right sides.

[0084] Accordingly, even when the stack 100 is pressed by the stack presser 81 from the surface of the stack 100, the stack 100 is not damaged by the belt 81C, and the stack 100 is configured to be slidable in the A direction in a state where the stack 100 is sandwiched between the placing table 11 provided with the lower roller 11A.

[0085] Further, an air cylinder 83 and four links 82A constituting the link mechanism 82 are rotatably connected to the support member 81A, whereby the support member 81A is configured to be rotatable. Further, the air cylinder 83 is connected near the center of the support member 81A, and the four links 82A are connected in two each in the front and rear. Further, an encoder 84 is attached to any one of these links 82A.

[0086] And, by these configurations, the measurement of the stack thickness by the stack thickness measuring means 80 in the present embodiment fixes the distance between the bottom surface of the stack during the sewing operation and the bottom surface of the stack presser 81 in the standby state retracted upward as a reference distance. Then, when the stack presser 81 moves to a position where it contacts the surface of the stack at the start of the sewing operation of the stack, the encoder 84 converts the rotation amount of the link of the link mechanism 82 into a moving distance in the height direction, subtracts the moving distance from the reference distance, and measures the stack thickness.

[0087] Note that, without using the above-described reference distance, the measurement value in a state where the stack presser 81 contacts the surface of the stack may be measured as the stack thickness with the bottom surface of the stack presser 81 reaching the position of the bottom surface of the stack as the origin of the moving distance. In addition, various methods are conceivable, such as measurement by a photoelectric sensor that detects the distance by the amount of reflection from the upper part to the lower part of the stack, measurement from the side part of the stack, and measurement by attaching a slit and a photomicro sensor to the stack presser 81. However, the above configuration is preferable in terms of not interfering during sewing.

[0088] In addition, the tatami sewing device 1 is provided with control means for adjusting the sewing height direction and depth direction of the sewing needle. Note that this control means is realized by a computer composed of components such as I / O, CPU, ROM, RAM, SDD, and peripheral circuits (not shown). And this computer is mounted inside the operation panel 90 shown in FIG. 9, and the aforementioned sewing machine main body 10, tatami thickness measuring means 80, etc. are connected to this computer by cables.

[0089] Note that the computer is not limited to being inside the operation panel 90 and may be arranged in another place, and the number of computers is not limited to one, and a configuration in which a plurality of computers are arranged in various places may also be adopted.

[0090] By the control means of this computer, the sewing height direction and depth direction of the sewing needle 112 are controlled. Also, by this computer, the measurement of the thickness of the tatami 100 by the tatami thickness measuring means 80 is also performed.

[0091] Specifically, based on the tatami thickness measured by the above-described measurement method of the tatami thickness measuring means 80, the operation of the elevator mechanism motor 40 is controlled, and the sewing height direction and depth direction of the sewing needle 112 along the tatami thickness are adjusted.

[0092] Thereby, it is possible to surely sew according to the thickness of the tatami 100, and prevent the sewing needle from interfering with other parts and breaking, being in a position where sewing cannot be performed, or the seam being dirty and finished.

[0093] In addition, the tatami sewing device 1 of the present embodiment is provided with determination means for determining whether or not the position of the sewing needle 112 is within the range of an appropriate sewing position, and failure prevention means for preventing failure when it is not within the range of the appropriate sewing position. These determination means and failure prevention means are also realized by the aforementioned computer.

[0094] This determination means determines whether the positions of the sewing needle 112 in the height direction and the depth direction of sewing are within the range of appropriate sewing positions based on the thickness of the tatami measured by the tatami thickness measuring means 80. When it is determined that the sewing needle 112 is not within the range of appropriate sewing positions, a warning is displayed on the display of the operation panel, and a warning lamp 91 at the upper part of the operation panel blinks.

[0095] Thereby, when the positions of the sewing needle 112 in the height direction and the depth direction of sewing are not within the allowable range, it can be prevented that the sewing needle 112 interferes with other parts and breaks, that the sewing machine malfunctions because the tatami edge cannot be sewn, and that even if it can be sewn, the seam will be dirty when finished.

[0096] When the warning lamp 91 blinks, the operator adjusts it by manually moving the position of the sewing needle 112 to an appropriate position or operating the operation panel.

[0097] (3. Other Embodiments) As described above, the preferred embodiments of the present invention have been described. Of course, the present invention is not limited to the above-described embodiments, and various modification examples or correction examples within the scope described in the claims also belong to the technical scope of the present invention.

[0098] In the above embodiment, although not particularly limited, the tatami sewing device of this embodiment can also be configured to be compatible with both half-tatami and one-tatami.

[0099] In the above embodiment, it is described by taking an example of use in the double-stitch process, but it can also be used in the border-stitch process.

[0100] The sewing needle is arc-shaped, but it may also be a straight needle. In the case of an arc shape, the reciprocating motion is a swinging and turning motion, while in the case of a straight needle, the reciprocating motion is a linear reciprocating motion.

Explanation of Reference Numerals

[0101] 1 Tatami sewing device 10 Sewing machine body 11 Placing table 11A Roller 12 Frame 13 Tatami edge supply reel 20 Sewing mechanism 21 Sewing machine arm 22 Needle arm 23 Cam 24 Connecting member 25 Motor for sewing mechanism 26 Presser foot 30 Lifting mechanism 40 Motor for lifting mechanism 50 Handle 51 Handle shaft 52 Sprocket 60 Chain 70 Balance 71 Guide roller 80 Tatami thickness measuring means 81 Tatami presser 81A Support member 81B Pulley 81C Belt 82 Link mechanism 83 Air cylinder 84 Encoder 90 Operation panel 91 Warning lamp 100 Tatami 110 Side 112 Sewing needle 113 Sewing needle drive shaft 211 Sewing machine swivel shaft 221 Sewing needle swing shaft 261 Presser foot shaft 262 Presser foot rotation drive shaft 263 Bevel gear 701 Balance drive shaft

Claims

1. A tatami sewing device for performing a return stitch or a hemming stitch on the side of a tatami and sewing a tatami edge to the side of the tatami, comprising: A sewing mechanism equipped with a sewing needle having a hole for inserting the upper thread, and performing a sewing operation on the tatami by swinging the sewing needle; A lifting mechanism for raising and lowering the position of the sewing needle; The lifting mechanism: Has a motor for the lifting mechanism to drive the lifting mechanism; The sewing mechanism: A sewing machine pivot axis serving as the pivot axis of the sewing mechanism; A sewing needle drive shaft for driving the sewing needle; A motor for the sewing mechanism for driving the sewing needle; Characterized in that based on the rotation of the motor for the lifting mechanism, the sewing height direction and the sewing depth direction of the sewing needle can be adjusted simultaneously; A tatami sewing device.

2. The tatami sewing device according to claim 1, characterized in that the sewing machine pivot axis of the sewing mechanism and the sewing needle drive shaft are on the same axis.

3. The sewing mechanism: A sewing needle swing axis on which the sewing needle swings; A connecting member and / or a cam mechanism connecting the sewing needle drive shaft and the swing axis; The tatami sewing device according to claim 2.

4. The sewing mechanism: Has a bobbin accommodating a bobbin wound with the lower thread, and a shuttle that is rotationally driven in conjunction with the drive of the sewing needle; Characterized in that a shuttle rotation drive shaft for rotationally driving the shuttle is on the same axis as the sewing needle drive shaft; The tatami sewing device according to claim 1.

5. The sewing mechanism: Characterized in that the shuttle rotation drive shaft is on the same axis as the sewing machine pivot axis and the sewing needle drive shaft; The tatami sewing device according to claim 4.

6. The sewing mechanism has a balance for pulling up the upper thread; The balance is arranged at a position close to the end side opposite to the end side where the sewing needle is located; Characterized in that a balance drive shaft for driving the balance is on the same axis as the sewing machine pivot axis; The tatami sewing device according to claim 1.

7. The sewing mechanism: Characterized in that the balance drive shaft is on the same axis as the sewing machine pivot axis and the sewing needle drive shaft; The tatami sewing device according to claim 6.

8. The sewing mechanism: Has a bobbin accommodating a bobbin wound with the lower thread, and a shuttle that is rotationally driven in conjunction with the drive of the sewing needle. A shuttle rotation drive shaft for rotationally driving the shuttle is characterized in that the sewing machine pivot axis, the sewing needle drive shaft, and the balance drive shaft are on the same axis; The tatami sewing device according to claim 7.

9. A motor for the sewing mechanism is disposed at the end of the sewing mechanism; The motor for the sewing mechanism and the sewing machine turning shaft are connected by a sprocket or a belt. The arrangement of the motor for the sewing mechanism, the sewing machine turning shaft, the sewing needle drive shaft, and the sewing needle swing shaft is fixed, and the motor for the sewing mechanism also moves up and down according to the up and down movement of the position of the sewing needle. The tatami sewing device according to claim 3.

10. The sewing machine turning shaft is provided near the center of the sewing mechanism. The tatami sewing device according to any one of claims 1 to 9.

11. The sewing needle is arranged on one end side of the sewing mechanism with respect to the sewing machine turning shaft. The balance is arranged on the other end side of the sewing mechanism with respect to the sewing machine turning shaft. The tatami sewing device according to claim 10, which depends on claims 8 and 9.

12. The motor for the lifting mechanism is a servo motor. The tatami sewing device according to claim 1.

13. The tatami sewing device further includes tatami thickness measuring means capable of measuring the thickness of the tatami. The tatami thickness measuring means has a tatami presser that moves up and down, and lifting means for lifting and lowering the tatami presser, and measures the thickness of the tatami by using the moving distance of the tatami presser. The tatami sewing device according to claim 1.

14. The tatami thickness measuring means uses the distance between the position of the bottom surface of the tatami and the upper limit position of the tatami presser in the standby state as a reference distance, subtracts the moving distance from the reference distance until the tatami presser abuts against the tatami surface and stops, and is means for measuring the thickness of the tatami. The tatami sewing device according to claim 13.

15. The lifting means has a drive means and a link mechanism connected to the presser, and an encoder attached to the link mechanism, and measures the thickness of the tatami by converting the rotation amount of the link constituting the link mechanism by the encoder into a distance in the height direction to obtain the moving distance of the tatami presser. The sewing device according to claim 13 or 14.

16. Based on the thickness of the tatami measured by the tatami thickness measuring means, by controlling the motor for the lifting mechanism, control means for adjusting the sewing height direction and depth direction of the sewing needle is provided. The tatami sewing device according to claim 13.

17. Based on the thickness of the tatami measured by the tatami thickness measuring means, determination means for determining whether the position of the sewing needle in the sewing height direction and depth direction is within the range of an appropriate sewing position, and failure prevention means for preventing failure when it is not within the range of the appropriate sewing position are provided. The tatami sewing and attaching device according to claim 13.

Images