JP7685229B2 - Tatami mat sewing device - Google Patents

Description

Application of Article 30, Paragraph 2 of the Patent Act Delivered via online seminar on August 21, 2021 (seminar name: TKC Online Seminar IN Summer)

An embodiment of the present invention relates to a sewing device for tatami mats.

In a tatami mat sewing device that can automatically sew tatami mat frames, the height at which the sewing needle is inserted into the tatami mat may be changed to accommodate changes in the thickness of the tatami mat or to change the type of stitch. Conventionally, methods for changing the height at which the sewing needle is inserted into the tatami mat include changing the cam itself that moves the sewing needle up and down, or changing the range of the sewing needle's oscillation. However, both methods require the operator to make mechanical adjustments manually, which is cumbersome and time-consuming. In addition, because the type of stitch is determined by the cam that moves the sewing needle up and down, changing the type of stitch requires the particularly time-consuming task of changing the cam.

JP 2006-394 A

This embodiment was made in consideration of the above circumstances, and its purpose is to provide a tatami mat sewing device that can reduce the workload of the worker and improve work efficiency.

The tatami sewing device includes a platform on which a tatami mat can be placed, a movement mechanism that can move in a linear direction along the platform, a sewing mechanism that is attached to the movement mechanism and can sew the tatami mat by swinging the sewing needle, a lifting mechanism motor that is attached to the movement mechanism and is composed of a servo motor that can control the rotational position of the motor shaft, and a lifting mechanism that is attached to the movement mechanism and converts the rotational force of the lifting mechanism motor into a vertical movement force and transmits it to the sewing mechanism, thereby changing the vertical position of the insertion and removal of the sewing needle from the tatami mat.

FIG. 1 is a plan view showing a schematic configuration of an example of a tatami mat sewing device according to a first embodiment; FIG. 1 is a side view showing a schematic configuration of an example of a tatami mat sewing device according to a first embodiment; FIG. 1 is a front view showing a schematic configuration of an example of a tatami mat sewing device according to a first embodiment, illustrating a case where the height position for inserting and removing a sewing needle is set to the highest position; FIG. 1 is a front view showing a schematic configuration of an example of a tatami mat sewing device according to a first embodiment, illustrating a case where the height position for inserting and removing a sewing needle is set to the lowest position; FIG. 1 is an enlarged view of the configuration of the cutting mechanism and its surroundings in an example of a tatami mat sewing device according to a first embodiment, showing a state in which a blade moving member is in a retracted position. FIG. 1 is an enlarged view of the configuration of the cutting mechanism and its surroundings in an example of a tatami mat sewing device according to a first embodiment, showing a state in which a blade moving member is in a pushed-out position. FIG. 1 is a block diagram showing an electrical configuration of an example of a tatami mat sewing device according to a first embodiment. A timing chart showing an example of a cutting process executed by the tatami mat sewing device according to the first embodiment. FIG. 1 is a diagram conceptually illustrating an operation status of the device main body in each step in an example of a cutting process performed by the tatami mat sewing device according to the first embodiment. FIG. 11 is a plan view showing a schematic configuration of an example of a tatami mat sewing device according to a second embodiment. FIG. 11 is a block diagram showing the electrical configuration of an example of a tatami mat sewing device according to a second embodiment.

Several embodiments will be described below with reference to the drawings. Note that elements that are essentially the same in each embodiment will be given the same reference numerals and descriptions will be omitted.

First Embodiment
The tatami sewing device 1 shown in Figure 1 is a device for sewing the frames of tatami mats, i.e., a device for sewing a tatami facing to the side surface in the thickness direction of a tatami mat bed. First, the mechanical structure of the tatami sewing device 1 will be explained with reference to Figures 1 to 6. As shown in Figures 1 to 4, the tatami sewing device 1 comprises a device main body 2 and a mounting table 10. The mounting table 10 is a table on which the tatami mat 90 to be sewn is placed. In this case, the tatami mat 90 is configured, for example, by wrapping a tatami facing around the front and sides of the tatami mat bed and part of the back surface.

The mounting table 10 can be configured to have a frame portion 11, a mounting portion 12, and a guide portion 13. The frame portion 11 is an element that constitutes the main part of the mounting table 10, and can be configured, for example, by combining multiple steel sections. The mounting portion 12 is configured, for example, from a flat steel plate, and is provided at the upper end of the frame portion 11. The tatami mat 90 to be sewn is placed on the mounting portion 12. The guide portion 13 has the function of guiding the movement of the device main body 2. The guide portion 13 can be configured, for example, from a rack gear that extends over the entire movement range of the device main body 2. In this case, the movement direction of the device main body 2 is determined by the extension direction of the guide portion 13.

The device body 2 has the function of sewing a tatami surface onto the side of the tatami bed 90 while moving in a linear direction along the tatami bed 90 placed on the placement table 10. In this specification, the tatami bed is referred to as a tatami mat 90 regardless of whether a tatami surface is sewn onto the tatami bed. The device body 2 includes a moving mechanism 20, a sewing mechanism 30, a lifting mechanism 40, a cutting mechanism 50, a moving mechanism motor 61, a sewing mechanism motor 62, and a lifting mechanism motor 63.

2 and other figures, the moving mechanism 20 is a stand on which the sewing mechanism 30, lifting mechanism 40, cutting mechanism 50, moving mechanism motor 61, sewing mechanism motor 62, and lifting mechanism motor 63 are mounted. The moving mechanism 20 has the function of linearly moving the sewing mechanism 30, lifting mechanism 40, and cutting mechanism 50 along the edge of the placement section 12, i.e., the edge of the tatami mat 90. The moving mechanism motor 61, sewing mechanism motor 62, and lifting mechanism motor 63 are also provided in the moving mechanism 20 and move together with the moving mechanism 20. In the following description, the direction in which the moving mechanism 20 moves when sewing the tatami mat 90, i.e., the direction from the start of sewing to the end of sewing, is referred to as the forward direction, and the opposite direction to the forward direction, i.e., the direction from the end of sewing to the start of sewing, is referred to as the backward direction.

As shown in Figs. 2 to 4, the moving mechanism 20 has a frame body 21, wheels 22, and a drive unit 23. The frame body 21 is formed by combining, for example, structural steel, an aluminum frame, and a plate material. The wheels 22 are provided at the four corners of the lower part of the frame body 21, and support the moving mechanism 20 so that it can move linearly. The drive unit 23 has a function of moving the moving mechanism 20 along the guide unit 13 by cooperating with the guide unit 13. When the guide unit 13 is formed of a rack gear, the drive unit 23 can be formed of a drive gear that meshes with the guide unit 13. In this case, the moving mechanism motor 61 can be formed of an electric motor that rotates the drive gear 23. The drive unit 23 is connected to the rotation shaft of the moving mechanism motor 61 and meshes with the guide unit 13. Therefore, when the moving mechanism motor 61 is driven, the moving mechanism 20 moves linearly along the guide unit 13.

The sewing mechanism 30 is a mechanism for sewing the frame of the tatami mat 90, and is provided on the moving mechanism 20. The sewing mechanism 30 performs sewing by swinging when driven by a motor 62 for the sewing mechanism. The motor 62 for the sewing mechanism is provided at the bottom of the moving mechanism 20, and can be configured, for example, by an electric motor. The sewing mechanism 30 can have a well-known configuration. The sewing mechanism 30 can be configured, for example, by having a swinging member 31, a needle arm 32, a guide arm 33, a cam 35, a first joint member 361, a second joint member 362, a needle hook (not shown), etc.

The oscillating member 31 is made of, for example, a casting, and has an oscillating shaft 311. The oscillating shaft 311 is configured so as not to move relative to the frame body 21. The oscillating member 31 is configured so as to be oscillable about the oscillating shaft 311. The oscillating member 31 oscillates, changing the height position at which the sewing needle N is inserted and removed from the tatami mat 90. The needle arm 32 is configured so as to be oscillable relative to the oscillating member 31, and is configured so that the sewing needle N can be attached. The guide arm 33 is provided so as not to move relative to the oscillating member 31. The guide arm 33 has the function of guiding the movement of the sewing needle N and preventing the position of the sewing needle N from shifting.

The cam 35 rotates by receiving power from the sewing mechanism motor 62, and swings the swinging member 31 and the needle arm 32. The sewing mechanism motor 62 can be, for example, an electric motor. The sewing mechanism motor 62 is connected to the cam 35 via a transmission member 621 such as a chain or belt, a sprocket 622, and gears (not shown). Therefore, the rotational force generated by the sewing mechanism motor 62 is transmitted to the cam 35 via the transmission member 621, the sprocket 622, and gears (not shown).

The first joint member 361 connects the cam 35 and the oscillating member 31, and has the function of oscillating the oscillating member 31 along the shape of the cam 35. In other words, the height position at which the sewing needle N is inserted and removed from the tatami mat 90 moves up and down along the external shape of the cam 35 as the cam 35 rotates. The second joint member 362 connects the cam 35 and the needle arm 32, and has the function of oscillating the needle arm 32 as the cam 35 rotates.

The lifting mechanism 40 is driven by the driving force of the lifting mechanism motor 63. As shown in Figures 3 and 4, the lifting mechanism 40 converts the rotational force of the lifting mechanism motor 63 into a vertical movement force and transmits it to the sewing mechanism 30, thereby swinging the sewing mechanism 30 and changing the height position of the sewing needle N relative to the tatami mat 90. In the following description, the highest position within the range of the height position of the sewing needle N relative to the tatami mat 90 that can be changed by the lifting mechanism 40 is sometimes referred to as the highest position Hh, and the lowest position is sometimes referred to as the lowest position Hl.

The lifting mechanism motor 63 is, for example, a servo motor that can electrically control the rotational position of the motor shaft 631. That is, as shown in FIG. 7, the lifting mechanism motor 63 has an internal encoder 632 and has the function of outputting the rotational angle of the motor shaft 631. Therefore, by precisely controlling the rotational position of the motor shaft 631, the lifting mechanism motor 63 can adjust the height position of the sewing needle N for insertion and removal from the tatami mat 90 in increments of a specified unit, for example, in increments of 1 mm, between the highest position Hh and the lowest position Hl.

The lifting mechanism 40 is configured to have, for example, multiple link members 41, 42, 43, and 44. In this embodiment, the lifting mechanism 40 is configured to have four link members 41, 42, 43, and 44. In the following description, the four link members 41, 42, 43, and 44 may be referred to as the driving side link member 41, the connecting link member 42, the driven side link member 43, and the action link member 44, in order from the side closest to the motor shaft 631.

The driving side link member 41 is connected to the motor shaft 631 of the lifting mechanism motor 63 and rotates integrally with the motor shaft 631. That is, one end of the driving side link member 41 is connected to the motor shaft 631. The driving side link member 41 is configured to be rotatable around the motor shaft 631. The connecting link member 42 is rotatably connected to the driving side link member 41 and the driven side link member 43. In this case, one end of the connecting link member 42 is rotatably connected to the driving side link member 41. The other end of the connecting link member 42 is rotatably connected to the driven side link member 43.

The driven link member 43 is connected to the connecting link member 42 and is configured to be rotatable while maintaining parallelism with respect to the driving link member 41. In this case, one end of the driven link member 43 is rotatably connected to the base body 21. That is, the driven link member 43 is configured to be rotatable around the connection part with the base body 21 as a fulcrum. As a result, part of the weight of the sewing mechanism 20 is supported by the base body 21, so that the load on the lifting mechanism motor 63 can be reduced. In other words, the lifting mechanism motor 63 can be small and has a small output. The other end of the driven link member 43 is rotatably connected to the action link member 44.

The action link member 44 is rotatably connected to the driven link member 43 and to the swinging member 31. The action link member 44 is connected to a location on the swinging member 31 that is as far away from the swinging shaft 311 as possible. The action link member 44 is also connected to a location on the swinging member 31 that is outside a circle that has the swinging shaft 311 as its center and a line connecting the swinging shaft 311 and the center of gravity of the swinging member 31 as its radius.

In this configuration, for example, when the motor shaft 631 rotates counterclockwise in FIG. 3, the connection portion of the swinging member 31 with the action link member 44 is pulled down as shown in FIG. 4, thereby lowering the height position at which the sewing needle N is inserted and removed from the tatami mat 90. Also, for example, when the motor shaft 631 rotates clockwise in FIG. 4, the connection portion of the swinging member 31 with the action link member 44 is pushed up as shown in FIG. 3, thereby raising the height position at which the sewing needle N is inserted and removed from the tatami mat 90. And, by controlling the rotational position of the motor shaft 631, the height position at which the sewing needle N is inserted and removed can be adjusted to any position.

The cutting mechanism 50 is removably equipped with a blade B for cutting the sewing thread. As shown in Figures 5 and 6, the cutting mechanism 50 has the function of automatically cutting the sewing thread after sewing the frame by moving the blade B toward and away from the tatami mat 90. As shown in Figure 2, the cutting mechanism 50 is attached to the front side of the moving mechanism 20 in the forward direction. The blade B can be, for example, a commercially available product, and can be replaced if it becomes worn out through use.

As shown in Figures 5 and 6, for example, the cutting mechanism 50 is configured to have a blade movement member 51, a linear drive unit 52, a linear guide unit 53, and a cover unit 54. The blade movement member 51 can detachably mount the blade B for cutting the sewing thread. The blade movement member 51 is configured to be movable horizontally and linearly in directions toward and away from the tatami mat 90. In other words, the blade movement member 51 is configured to be movable horizontally and in a direction perpendicular to the movement direction of the movement mechanism 20.

In the following description, the direction in which the blade moving member 51 approaches the tatami mat 90 may be referred to as the push direction, and the direction in which the blade moving member 51 moves away from the tatami mat 90 may be referred to as the retract direction. In this embodiment, pushing out the blade moving member 51 means that the blade moving member 51 is pushed out from the moving mechanism 20 side. Retracting the blade moving member 51 means that the blade moving member 51 is retracted into the moving mechanism 20 side. In the following description, the end of the blade moving member 51 on the push direction side may be referred to as the tip, and the end on the retract direction side may be referred to as the base.

The blade moving member 51 is formed, for example, by cutting and bending a metal plate. The tip of the blade moving member 51 is formed in a shape similar to the Roman numeral "7" when viewed from the forward direction side of the movement mechanism 20. The blade moving member 51 has a return portion 511 and an inclined portion 512. The return portion 511 is provided at the very tip of the blade moving member 51 and is formed in a shape that extends downward in the retraction direction. The return portion 511 has the function of hooking the sewing thread when the blade moving member 51 is moved in the retraction direction.

The inclined portion 512 is provided near the tip of the blade moving member 51, closer to the base end than the return portion 511. The blade B is attached to the upper end portion of the return portion 511 and the inclined portion 512. The inclined portion 512 is formed in a shape that extends downward in the extrusion direction, and extends below the return portion 511. The inclined portion 512 has the function of guiding the sewing thread to the return portion 511 and the blade B when the blade moving member 51 is moved in the extrusion direction. In other words, when the blade moving member 51 moves in the extrusion direction and comes into contact with the inclined portion 512, the sewing thread rises along the inclined portion 512 and is guided to the return portion 511 and the blade B.

The linear actuator 52 has a function of generating power for linearly moving the blade moving member 51 in the push-out direction and the retraction direction. The linear actuator 52 can be configured with a linear actuator such as an air cylinder, an electric cylinder, or a solenoid actuator. The linear actuator 52 is not limited to a linear actuator, and may be configured to convert a rotational force into a linear driving force, such as a rack gear and a pinion gear. The linear guide 53 is for guiding the linear movement of the blade moving member 51 to make the movement smooth, and can be configured with a so-called linear guide or linear shaft. For example, if the linear actuator 52 can ensure the movement accuracy of the blade moving member 51, the linear guide 53 does not necessarily have to be provided.

As shown in FIG. 5, the cover 54 has the function of covering the periphery of the blade B to prevent the operator's fingers from touching it when the blade moving member 51 is moving in the retracting direction. In this case, as shown in FIG. 6, the blade B is exposed from the cover 54 only when the blade moving member 51 is moving in the pushing direction. The cover 54 can be made of, for example, a metal or resin, half-cut cylindrical member.

Next, the electrical configuration of the tatami sewing device 1 will be described with reference to FIG. 7. The electrical configuration of the tatami sewing device 1 includes a linear drive unit 52, a motor 61 for the movement mechanism, a motor 62 for the sewing mechanism, a motor 63 for the lifting mechanism, as well as a needle position sensor 64, a servo amplifier 65, a control panel 70, and an operation panel 80. The needle position sensor 64 and the servo amplifier 65 are provided in the movement mechanism 20. The needle position sensor 64 has the function of detecting the position of the sewing needle N. In other words, the needle position sensor 64 can detect whether the sewing needle N is inserted into or removed from the tatami mat 90.

The servo amplifier 65 receives a feedback signal from the encoder 632 built into the lifting mechanism motor 63, and receives at least one target value command for the position, speed, or rotational force of the motor shaft 631 from the control device 71 of the control panel 70, and controls the output of the lifting mechanism motor 63 based on these feedback signals and target value commands.

The control panel 70 can be configured, for example, separately from the device main body 2, or can be provided in the device main body 2. That is, the control panel 70 can be provided, for example, in a location other than the moving mechanism 20, or can be provided in the moving mechanism 20. The control panel 70 has a control device 71. The control device 71 is mainly configured with a microcomputer having a CPU 711 and a storage area 712 such as ROM, RAM, and non-volatile memory. The control device 71 has a function of managing the operation of the entire tatami mat sewing device 1. The control device 71 can be configured, for example, with a programmable controller. The linear drive unit 52, the moving mechanism motor 61, the sewing mechanism motor 62, the lifting mechanism motor 63, the needle position sensor 64, and the servo amplifier 65 are connected to the control device 71 directly or indirectly via other devices.

The operation panel 80 has the function of accepting various input operations from the operator of the tatami sewing device 1 regarding the settings of the tatami sewing device 1, and presenting various information to the worker. The worker can operate the operation panel 80 to set the thickness dimension of the tatami mat 90, the height position for inserting and removing the sewing needle N, and the type of stitches. The operation panel 80 can be configured with, for example, an input unit 81 and an output unit 82. The input unit 81 can be configured with, for example, a switch or a touch panel that can be operated by the worker. The output unit 82 can be configured with, for example, a display that presents information in the form of images or characters, or a speaker that presents information in the form of sound. The operation panel 80 can be configured, for example, separately from the device main body 2 and the control panel 70, or it can be provided in the device main body 2 and the control panel 70.

The control panel 70 also has a lifting/lowering processing section 72, a sewing operation processing section 73, and a cutting processing section 74. The lifting/lowering processing section 72, the sewing operation processing section 73, and the cutting processing section 74 have the function of controlling the electrical configuration of the moving mechanism motor 61, the sewing mechanism motor 62, the lifting mechanism motor 63, the needle position sensor 64, and the servo amplifier 65, etc., to perform a predetermined function. For example, the memory area 712 of the control device 71 stores a program for realizing the lifting/lowering processing section 72, the sewing operation processing section 73, and the cutting processing section 74. The control device 71 virtually realizes the lifting/lowering processing section 72, the sewing operation processing section 73, and the cutting processing section 74 by software by executing the above program stored in the memory area 712 in the CPU 711. Note that the lifting/lowering processing section 72, the sewing operation processing section 73, and the cutting processing section 74 may be realized in hardware as an integrated circuit integrated with the control device 71.

The lifting/lowering processing unit 72 is capable of executing lifting/lowering processing. The lifting/lowering processing includes a process of changing the height position for inserting and removing the sewing needle N by driving the motor 63 for the lifting mechanism based on an operation input to the input unit 81 to swing the sewing mechanism 30. In this case, the lifting/lowering processing unit 72 accepts the height position for inserting and removing the sewing needle N in units of, for example, 1 mm. This allows the worker to adjust the height position for inserting and removing the sewing needle N in units of, for example, 1 mm, to match the thickness dimension of the tatami mat 90.

For example, when the needle position sensor 64 detects that the sewing needle N has been removed from the tatami mat 90, the lifting/lowering processing unit 72 allows the lifting/lowering mechanism motor 63 to be driven. In addition, when the lifting/lowering processing unit 72 does not detect that the sewing needle N has been removed from the tatami mat 90, in other words, when it detects that the sewing needle N is inserted into the tatami mat 90, it does not allow the lifting/lowering mechanism motor 63 to be driven. This prevents the sewing needle N from moving up or down while inserted into the tatami mat 90 and becoming caught in the tatami mat 90 and being damaged.

The sewing operation processing unit 73 can execute sewing operation processing. The sewing operation processing includes processing for executing the operation of sewing the frame of the tatami mat 90 by driving each motor 61, 62, 63 based on information set via the operation panel 80. The sewing operation processing unit 73 can change the height position of the insertion and removal of the sewing needle N by driving the motor 63 for the lifting mechanism in accordance with the swinging of the sewing needle N and the movement of the movement mechanism 20. This allows the sewing operation processing unit 73 to sew not only straight stitches in which the height position of the insertion and removal of the sewing needle N does not change, but also ladder stitches and trapezoidal stitches in which the height position of the insertion and removal of the sewing needle N is changed.

The cutting processing unit 74 is capable of executing a cutting process. The cutting process includes a process of driving the cutting mechanism 50 to cut the sewing thread, for example, after the frame of the tatami mat 90 has been sewn, either automatically or in response to an operator operating the operation panel 80. As shown in Figures 8 and 9, the cutting process includes a lowering step S1, a drawing out step S2, a loosening step S3, an approaching step S4, a tensioning step S5, and a cutting step S6. When executing the cutting process, the cutting processing unit 74 executes the lowering step S1, the drawing out step S2, the loosening step S3, the approaching step S4, the tensioning step S5, and the cutting step S6 in that order.

In FIG. 9, the sewing end position Pe indicates the horizontal position at the end of the sewing operation process, i.e., the position at which the sewing needle N is passed through the tatami mat 90 at the end of the sewing operation process. Also in FIG. 9, the current horizontal position of the sewing needle N is shown as the sewing needle position PN. In this case, at the end of the sewing operation process, the sewing thread 91 extends from the sewing end position Pe through the sewing needle position PN to the sewing thread 91 supply section 24.

The cutting processing unit 74 first executes a pre-processing step S0 before executing the cutting process. The pre-processing step S0 is a step in which the needle position sensor 64 determines whether or not the sewing needle N has come out of the tatami mat 90. When the needle position sensor 64 detects that the sewing needle N has come out of the tatami mat 90, the cutting processing unit 74 executes the cutting process.

When the cutting processing unit 74 executes the cutting process, it first executes the lowering step S1. The lowering step S1 is a step in which the motor 63 for the lifting mechanism is driven to lower the sewing needle N below the underside of the tatami mat 90. That is, when the cutting processing unit 74 executes the lowering step S1, it drives the motor 63 for the lifting mechanism to lower, or retract, the sewing needle N to a position where it does not interfere with the tatami mat 90.

Next, the cutting processing unit 74 executes the pulling-out process S2. The pulling-out process S2 is a process of pulling out the sewing thread 91 from the sewing thread 91 supply unit 24 by moving the moving mechanism 20 in a direction away from the sewing end position Pe. In this embodiment, the cutting processing unit 74 moves the moving mechanism 20 in the backward direction in the pulling-out process S2.

Next, the cutting processing unit 74 executes the loosening process S3. The loosening process S3 is a process for loosening the sewing thread 91 that was pulled out in the pulling out process S2 by moving the moving mechanism 20 in a direction approaching the sewing end position Pe. In other words, the loosening process S3 is a process for bending the sewing thread 91. In this embodiment, the cutting processing unit 74 moves the moving mechanism 20 in the forward direction. In this case, the movement distance of the moving mechanism 20 in the loosening process S3 is set to at least half the movement distance of the moving mechanism 20 in the pulling out process S2.

Next, the cutting processing unit 74 executes the approaching step S4. The approaching step S4 is a step of driving the linear drive unit 52 to push the blade moving member 51 in a direction approaching the tatami mat 90, and bringing the blade moving member 51 closer to the slackened sewing thread 91. In this case, the sewing thread 91 comes into contact with the inclined portion 512 of the blade moving member 51.

Next, the cutting processing unit 74 executes the tensioning step S5. The tensioning step S5 is a step of tensioning the sewing thread 91 by moving the moving mechanism 20 in a direction away from the sewing end position Pe. In this embodiment, the cutting processing unit 74 moves the moving mechanism 20 in the backward direction in the tensioning step S5. In this case, it is not necessary for the sewing thread 91 to completely lose its slack, and it is sufficient that the slack is less than at the time of the slackening step S3.

Then, the cutting processing unit 74 executes the cutting step S6. In the cutting step S6, the linear drive unit 52 is driven in the opposite direction to that in the approaching step S4, so that the blade moving member 51 is pulled in a direction away from the tatami mat 90, and the sewing thread 91 is cut by the blade B. Through this series of steps, the sewing thread 91 is automatically cut without the operator having to cut the sewing thread 91 with scissors or the like.

According to the embodiment described above, the tatami sewing device 1 includes a mounting table 10, a moving mechanism 20, a sewing mechanism 30, a motor 63 for the lifting mechanism, and a lifting mechanism 40. The mounting table 10 is configured so that the tatami 90 to be sewn can be placed on it. The moving mechanism 20 is configured so that it can move in a linear direction along the mounting table 10. The sewing mechanism 30 is provided on the moving mechanism 20, and can sew the tatami 90 placed on the mounting table 10 by attaching a sewing needle N and swinging the sewing needle N. The motor 63 for the lifting mechanism is provided on the moving mechanism 20, and is configured as a servo motor that can control the rotational position of the motor shaft 631. The lifting mechanism 40 is provided on the moving mechanism 20, and is configured so that the rotational force of the motor 63 for the lifting mechanism can be converted into a vertical moving force and transmitted to the sewing mechanism 20, thereby changing the vertical position of the insertion and removal of the sewing needle N relative to the tatami 90.

With this, the tatami sewing device 1 can adjust the height position of the insertion and removal of the sewing needle N relative to the tatami mat 90 by driving the motor 63 for the lifting mechanism, through the action of the movement mechanism 20. Therefore, when responding to changes in the thickness of the tatami mat 90 or when changing the type of stitch, the worker can change the height position of the insertion and removal of the sewing needle N without having to carry out the troublesome work of replacing a cam that determines the needle oscillation width or stitch type, such as the cam (31) shown in Figure 4 of Patent Document 1, or manually changing the oscillation range of the sewing needle N. This reduces the burden on the worker and improves work efficiency.

The lifting mechanism 40 has a driving side link member 41, a connecting link member 42, a driven side link member 43, and an action link member 44. The driving side link member 41 is connected to the motor shaft 631 of the lifting mechanism motor 63. The connecting link member 42 is rotatably connected to the driving side link member 41. The driven side link member 43 is rotatably connected to the connecting link member 42. And, the action link member 44 is rotatably connected to both the driven side link member 43 and the swinging member 31 of the sewing mechanism 30.

When connecting the motor shaft 631 of the lifting mechanism motor 63 and the oscillating member 31 with a link, it is also possible to connect the driving side link member 41 directly to the action link member 44 without going through the connecting link member 42 and the driven side link member 43. However, in this case, the driving side link member 41 and the action link member 44 become longer, which makes it difficult to secure the installation space. Furthermore, when the driving side link member 41 becomes longer, the difference in the vertical movement distance of the tip of the driving side link member 41 increases depending on the angle of the driving side link member 41, making control difficult.

On the other hand, according to this embodiment, the driving side link member 41 and the action link member 44 are connected via the connecting link member 42 and the driven side link member 43. Therefore, each link member 41, 42, 43, 44 can be made short, and the rotation radius of each link member 41, 42, 43, 44 can be reduced. As a result, it becomes easier to secure the installation space, and the increase in size of the device main body 2 due to the provision of the lifting mechanism 40 can be suppressed.

The tatami mat sewing device 1 also includes a cutting mechanism 50 that can automatically cut the sewing thread 91. The cutting mechanism 50 has a blade movement member 51. The blade movement member 51 is equipped with a blade B for cutting the sewing thread 91 and is configured to be able to move the blade B in a direction approaching and moving away from the tatami mat 90. As a result, the sewing thread 91 is automatically cut, eliminating the need for the worker to manually cut the sewing thread 91, and as a result, improving work efficiency.

The tatami mat sewing device 1 further includes a cutting processing section 74. The cutting processing section 74 can sequentially execute the lowering step S1, the pulling out step S2, the loosening step S3, the approaching step S4, the tensioning step S5, and the cutting step S6. The lowering step S1 is a step of driving the motor 63 for the lifting mechanism to lower the sewing needle N below the tatami mat 90. The pulling out step S2 is a step of moving the moving mechanism 20 in a direction away from the sewing end position Pe to pull out the sewing thread 91. The loosening step S3 is a step of moving the moving mechanism 20 in a direction approaching the sewing end position Pe to loosen the sewing thread 91 pulled out in the pulling out step S2. The approaching step S4 is a step of pushing the blade moving member 51 in a direction approaching the tatami mat 90 to bring the blade moving member 51 closer to the loosened sewing thread 91. The tensioning step S5 is a step of tensioning the sewing thread 91 by moving the moving mechanism 20 in a direction away from the sewing end position Pe. The cutting step S6 is a step of retracting the blade moving member 51 in a direction away from the tatami mat 90 and cutting the sewing thread 91 with the blade B.

In this way, the tatami mat sewing device 1 can reliably cut the sewing thread 91 with the blade portion B by sequentially executing the above steps S1 to S6.

Second Embodiment
Next, the second embodiment will be described with reference to Figures 10 and 11. The tatami sewing device 1a of the second embodiment is a device that can sew opposing frames of a tatami mat 90 at the same time. The tatami sewing device 1a further includes a device main body 3 in addition to the device main body 2 of the first embodiment. That is, the tatami sewing device 1a includes two device main bodies 2 and 3. The device main body 3 has a moving mechanism 20, a sewing mechanism 30, a motor 63 for the lifting mechanism, and a lifting mechanism 40, just like the device main body 2, and is configured symmetrically to the device main body 2. That is, the two device main bodies 2 and 3 are configured symmetrically with the mounting table 10 in between. In addition, both device main bodies 2 and 3 are connected to the control device 71 of the same control panel 70, and operate by receiving the same control command from the control device 71. That is, the device main bodies 2 and 3 are linked to each other and perform the same operation.

Here, in the case of a conventional configuration in which the insertion height position of the sewing needle N is manually changed, the operator is required to work on both device bodies 2 and 3 in order to change the insertion height position of the sewing needle N, which is time-consuming and difficult to work with. In contrast, according to this embodiment, the operator can simultaneously change the insertion height position of the sewing needle N for both device bodies 2 and 3 simply by operating the operation panel 80, for example. As a result, according to this embodiment, it is possible to significantly improve the workability when changing the insertion height position of the sewing needle N.

The above-described embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. The present embodiments and their modifications are within the scope and spirit of the invention, and are included in the scope of the invention and its equivalents as set forth in the claims.

1, 1a... Tatami sewing device, 2, 3... Device body, 10... Placement table, 20... Movement mechanism, 30... Sewing mechanism, 40... Lifting mechanism, 41... Driving link member, 42... Connection link member, 43... Driven link member, 44... Working link member, 50... Cutting mechanism, 51... Blade moving member, 63... Lifting mechanism motor, 631... Motor shaft, 90... Tatami, 91... Sewing thread, B... Blade, N... Sewing needle, S1... Lowering process, S2... Pulling out process, S4... Approaching process, S5... Stretching process, S6... Cutting process

Claims (4)

A platform on which a tatami mat can be placed;
a moving mechanism that is movable in a linear direction along the mounting table;
a sewing mechanism that is provided on the moving mechanism and has a sewing needle attached thereto, and that can sew the tatami mat by swinging the sewing needle;
a motor for a lifting mechanism, the motor being a servo motor provided in the moving mechanism and capable of controlling a rotational position of a motor shaft;
a lifting mechanism that is provided in the moving mechanism and converts the rotational force of the motor for the lifting mechanism into a vertical moving force and transmits it to the sewing mechanism, thereby changing a height position of the insertion and removal of the sewing needle from the tatami mat;
Equipped with
The lifting mechanism includes:
a drive side link member connected to the motor shaft of the lifting mechanism motor;
a connecting link member rotatably connected to the driving side link member;
a driven link member rotatably connected to the connecting link member;
an action link member rotatably connected to each of the driven link member and the sewing mechanism;
A sewing device for tatami mats having the above structure . The sewing machine further includes a cutting mechanism that has a blade moving member to which a blade for cutting the sewing thread is attached and that can move the blade in a direction approaching and away from the tatami mat, and that can automatically cut the sewing thread.
The tatami mat sewing device according to claim 1 . A platform on which a tatami mat can be placed;
a moving mechanism that is movable in a linear direction along the mounting table;
a sewing mechanism that is provided on the moving mechanism and has a sewing needle attached thereto, and that can sew the tatami mat by swinging the sewing needle;
a motor for a lifting mechanism, the motor being a servo motor provided in the moving mechanism and capable of controlling a rotational position of a motor shaft;
a lifting mechanism that is provided in the moving mechanism and converts the rotational force of the motor for the lifting mechanism into a vertical moving force and transmits it to the sewing mechanism, thereby changing a height position of the insertion and removal of the sewing needle from the tatami mat;
A cutting mechanism having a blade portion for cutting the sewing thread, the blade portion having a blade portion moving member that is attached to the blade portion and that can move the blade portion in a direction approaching and away from the tatami mat, and capable of automatically cutting the sewing thread;
Equipped with
a lowering step of driving a motor for the lifting mechanism to lower the sewing needle below the tatami mat;
a drawing step of drawing out the sewing thread by moving the moving mechanism in a direction away from a sewing end position;
a loosening step of moving the moving mechanism in a direction approaching the sewing end position to loosen the sewing thread pulled out in the pulling out step;
an approaching step of pushing the blade portion moving member in a direction approaching the tatami mat to bring the blade portion moving member closer to the slackened sewing thread;
a tensioning step of tensioning the sewing thread by moving the movement mechanism in a direction away from the sewing end position;
A cutting step of retracting the blade portion moving member in a direction away from the tatami mat to cut the sewing thread with the blade portion,
Sewing device for tatami mats. two device bodies each having the moving mechanism, the sewing mechanism, the lifting mechanism motor, and the lifting mechanism;
The two device bodies are configured symmetrically with respect to the mounting table.
The tatami mat sewing device according to any one of claims 1 to 3 .

Images