Sewing machine

Abstract

To improve operability of a sewing machine.SOLUTION: A sewing machine includes: a movement detection device 7 for detecting a movement amount of an object to be sewn; a drive motor 2 for operating a needle; a control device 100 for controlling the drive of the drive motor 2; and a storage device 102. The storage device 102 stores a sewing speed and a sewing pitch. The control device 100 can execute a first control mode for controlling the drive motor 2 at the stored sewing speed, in the case where the detection value by the movement detection device 7 has exceeded a predetermined first threshold value, and a second mode for controlling the drive motor 2 so that sewing is performed with the stored sewing pitch based on the detection value by the movement detection device 7 in the case where the detection value by the movement detection device 7 has exceeded a predetermined second threshold value, and these first control mode and second control mode of the control device 100 can be switched.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a sewing machine. [Background technology]

[0002] For example, Patent Document 1 proposes a sewing machine that is provided with a means for detecting the amount of movement of the cloth (distance measuring means in the publication) to detect the movement speed of the cloth, and controls the sewing speed (rotational speed of the sewing machine drive motor) according to the movement speed, thereby making it possible to sew with evenly spaced stitch pitches. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2002-292175 Summary of the Invention [Problem to be solved by the invention]

[0004] The sewing speed controlled according to the moving speed of the cloth, as in the sewing machine of Patent Document 1, may actually reduce workability depending on the type of sewing (for example, variable zigzag sewing in which the stitch pitch is purposely changed while sewing) and the skill and preference of the user. On the other hand, when the user adjusts the sewing speed for such workability, there is a problem that the operation becomes complicated. An object of the present invention is to reduce the complexity of a sewing machine without compromising operability, in accordance with various sewing types and the skills and preferences of users. [Means for solving the problem]

[0005] In order to solve the above problems, for example, the configurations described in the claims are adopted. The present application includes a number of configurations and methods for solving the above problems, one example of which relates to a sewing machine. The sewing machine includes at least a movement detection device that detects the amount of movement of a sewing object, a drive motor that operates a needle, a control device that controls the drive motor, and a storage device. The storage device stores a sewing speed and a sewing pitch, and the control device can execute a first control mode in which the drive motor is controlled at the stored sewing speed when a value detected by the movement detection device exceeds a predetermined first threshold, and a second control mode in which the drive motor is controlled at the stored sewing pitch based on the detection value by the movement detection device when a value detected by the movement detection device exceeds a predetermined second threshold, and the control device can switch between the first control mode and the second control mode. Effect of the Invention

[0006] According to this sewing machine, the control mode can be switched according to the type of sewing, etc., thereby improving operability. [Brief description of the drawings]

[0007] [Figure 1] 1 is an example of an external view showing an embodiment of a sewing machine. [Diagram 2] 1 is an example of an external view including a partial cross section showing an enlarged view of the area around the presser. [Diagram 3] FIG. 11 is an example of an external view showing another embodiment of a sewing machine. [Figure 4] FIG. 2 is a block diagram illustrating an example of a control device and a peripheral device. [Diagram 5] 11A to 11C are diagrams illustrating an example of sewing speed control in a first control mode. [Figure 6] 4 is an example of a flowchart illustrating a first embodiment of a first control mode executed by a control device. [Figure 7] 11A and 11B are diagrams illustrating an example of sewing speed control in a second control mode. [Figure 8] 5 is an example of a flowchart illustrating a first embodiment of a second control mode executed by the control device. [Figure 9]11 is an example of a flowchart illustrating a second embodiment of a first control mode executed by the control device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to specific examples.

[0009] FIG. 1 shows an embodiment of a sewing machine. The sewing machine 1 operates the needle 3 via a well-known link mechanism (not shown) from a built-in drive motor 2, and when the sewing object (not shown) held down by the presser foot 4 is moved by the user, the sewing machine 1 performs a sewing operation in synchronization with the movement (in the case of free motion sewing). The sewing operation crosses the upper thread and the lower thread (not shown) to form a stitch on the sewing object. The upper thread is provided from a thread spool (not shown) and passed through the needle 3. The lower thread is stored in a bobbin (not shown) and is housed inside the sewing machine 1. The sewing object (e.g., cloth) is clamped between the presser foot 4 and the needle plate 5. The needle 3 is lowered by the drive of the drive motor 2, passes through the sewing object and approaches the bobbin. The upper thread and the lower thread are entangled by the action of a shuttle (not shown), and when the needle 3 rises and comes out of the sewing object, a stitch is formed. In the case of normal sewing, which is not free motion, the sewing object is automatically fed forward a predetermined amount by the action of an automatic feed mechanism (not shown), and the next stitch is formed in the same manner. By repeating this operation, a continuous straight stitch pattern with stitches at predetermined intervals is sewn onto the workpiece. The stitch pitch is the distance between each stitch.

[0010] Free motion sewing is a technique in which the user performs the sewing operation of the sewing machine 1 while manually moving the workpiece, without using the above-mentioned automatic feed mechanism of the sewing machine 1, in order to obtain any sewing pattern of the user's choice, such as curved lines. The presser foot 4 shown in Figure 1 is a presser foot suitable for this free motion sewing. Figure 2 shows an enlarged view of the presser foot 4 in this example (the hatched portion is a cross section).

[0011] The presser foot 4 is provided with a presser portion 4a having a circular hole. The sewing object is placed between the presser portion 4a and the needle plate 5, and the needle 3 is inserted into the sewing object through the hole in the presser portion 4a. The presser portion 4a does not impede the up and down movement of the needle 3, and is located on the sewing object around the place where the needle 3 is inserted, so that the presser portion 4a suppresses the up and down flapping of the sewing object caused by the up and down movement of the needle 3, and helps to form a reliable stitch. The presser foot 4 is attached to a presser bar 6 that can move up and down in accordance with the movement of the needle 3. The presser foot 4 is detachable and can be replaced with a presser foot for normal sewing. It can be replaced with an appropriate presser foot when switching the mode of the sewing machine 1 between normal sewing and free motion sewing.

[0012] A sensor of a movement detection device 7 is incorporated in this presser foot 4, as shown in the cross section in FIG. 2. The movement detection device 7 for detecting the movement amount of the workpiece is configured using, for example, an image sensor, and information regarding the movement of the workpiece is obtained by image processing of the image data obtained by imaging the surface of the workpiece with the image sensor. Alternatively, an optical sensor can be used as the sensor of the movement detection device 7, and the optical sensor uses visible light or infrared light to read the surface shape of the workpiece and detect the movement amount of the workpiece. As another example, a movement detection device can be used that incorporates a trackball that comes into contact with the workpiece and detects the movement amount of the workpiece from the rotational movement of the trackball that moves in accordance with the movement of the workpiece.

[0013] In this example, the movement detection device 7 is incorporated in the detachable presser foot 4, but the movement detection device 7 including the sensor may be provided in the main body of the sewing machine 1. Furthermore, although an example in which the sensor is provided above the sewing object is shown, the sensor of the movement detection device 7 may be provided below the sewing object (for example, around the needle plate). Also, a movement detection device may be provided separately from the sewing machine 1 and attached to the hand or arm of the user to detect the movement of the user's hand or arm, thereby indirectly detecting the movement of the sewing object. Other possible movement detection devices include a movement detection device that is attached to the sewing object to detect the movement of the sewing object, and a movement detection device that works in conjunction with an app that uses a camera on a smartphone, tablet, or the like to detect the movement of the user's hand or the sewing object.

[0014] The sewing machine 1 is provided with a start / stop key 8, a speed controller 9, and a touch panel display device 10 at positions that are easy for the user to operate. The start / stop key 8 is for starting / stopping the sewing operation, and is configured as a push button in this example. The speed controller 9 is a slide knob in this example, and is an analog device whose output changes depending on the position to which the user slides the knob left or right. Although a slide knob is shown as an example, a rotary knob or the like may be used. Also, it may be implemented as a digital device that processes input as a digital signal. The display device 10 is, as an example, a touch panel type implemented using a liquid crystal panel display, and is used to display the functions and operating status of the sewing machine 1, and to touch input various parameters on a setting screen, etc. For example, the user can input settings for the sewing speed and stitch pitch by touching a predetermined area of ​​the display device 10 that displays the setting screen.

[0015] This sewing machine 1 is equipped with a needle left-right swing mechanism 20 (also called a needle swing mechanism) that swings (oscillation movement) the needle 3 left-right. By combining the oscillation movement of the needle 3 by the needle left-right swing mechanism 20 with the above-mentioned sewing operation and feed operation, it is possible to form a zigzag stitch with a stitch width (amplitude) W (zigzag stitch), for example, as shown in the partially enlarged view α in Fig. 1. Also, free motion variable zigzag stitching is possible, which allows zigzag stitching while changing the stitch width W with free motion stitching.

[0016] The needle left-right swing mechanism 20 is actuated by an amplitude motor 21, which is, for example, a stepping motor. Specifically, the needle left-right swing mechanism 20 has a gear that meshes with the gear of the amplitude motor 21, and swings around a rotary shaft 22 according to the rotation angle of the amplitude motor 21. The rotation angle of the amplitude motor 21, which in this example is the step angle of the stepping motor, is controlled as the drive amount of the amplitude motor 21. The needle left-right swing mechanism 20 holds a needle bar 23 that extends in the vertical direction, and the needle bar 23 swings in accordance with the swing of the needle left-right swing mechanism 20, thereby swinging the needle 3 attached to the needle bar 23. Therefore, the amplitude of the needle 3, i.e., the stitch width W, is controlled by controlling the drive amount of the amplitude motor 21.

[0017] The sewing machine 1 is provided with a knee operating device (herein referred to as a knee lifter) 30 as one of the operating devices operated by the user. The knee lifter 30 is an operating device provided so that a seated user can operate it by pressing a pad 31 with his / her knee (the right knee in the illustrated example). The knee lifter 30 rotates around an operating shaft 32 according to the user's operation, and the amount of rotation is detected by an encoder 33 as an operation amount and sent to a control device described later as an analog signal or a digital signal. The pad 31 is biased to an initial position by a return spring (not shown). The user operates the pad 31 against this biasing force, and when the user releases his / her knee, the pad 31 returns to the initial position by the biasing force. The knee lifter 30 does not require manual operation, so the user can operate it even during sewing. Therefore, the user can control the sewing by, for example, changing the stitch width W of a zigzag stitch by operating the knee lifter 30 during free motion sewing.

[0018] Furthermore, as shown in FIG. 3, a foot operation device (herein referred to as a foot controller) 40, which is one of the operation devices, can be connected to the sewing machine 1 through an input / output terminal. The foot controller 40 has a structure in which a treadle 42 is pivotally supported on a base 41 so that it can swing. The treadle 42 is biased so that it returns to its original position when the foot is released, and an output is generated by pressing the treadle 42 against the biasing force. An encoder 43 is built into the base 41 of the foot controller 40, and an output is obtained according to the amount of depression of the treadle 42. The output may be an analog signal or digital information. It is also possible to start a sewing operation by pressing the foot controller 40, stop the sewing operation by releasing it, and adjust the sewing speed according to the amount of depression.

[0019] For example, while sewing with variable zigzag stitching, the user needs to operate the knee lifter 30 and foot controller 40, and also needs to place his / her hand on the sewing material and move it in the sewing direction. Furthermore, when starting and finishing sewing, it is also necessary to operate a separate operation device such as the start / stop key 8. For this reason, the operation of variable zigzag stitching is generally complicated, and there is room for improvement in operability.

[0020] [Example of control device] 4 is a block diagram showing an embodiment of the control device 100 and its peripheral devices that are mounted on the sewing machine 1 and configured to control the sewing operation. The control device 100 is a processor (CPU) configured by, for example, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a PLC (Programmable Logic Controller), and controls the sewing operation by executing a computer program stored in an external or internal memory.

[0021] The control device 100 controls the operation device 101 and the display device 10, and receives signals output from the operation device 101 and the display device 10. The operation device 101 includes the start / stop key 8, the speed controller 9, the knee lifter 30, and the foot controller 40 described above. The control device 100 is further connected to a storage device 102. The storage device 102 has areas for storing a sewing speed Rset (set value), a first threshold value Vh1, a second threshold value Vh2, and a third threshold value Vh3 (corresponding to the threshold values ​​of the movement speed V of the sewing workpiece in this embodiment) of the detection value by the movement detection device 7, an acceleration time T, and an upper limit sewing speed Rlimit and a sewing start speed Rstart. The areas may be called a sewing speed setting device, a threshold value setting device, an acceleration time setting device, and an upper limit / start sewing speed setting device. In another embodiment, the sewing speed setting device, the threshold value setting device, the acceleration time setting device, and the upper limit / start sewing speed setting device may be separately prepared as hardware modules or software modules in addition to the storage device 102. In addition, each "apparatus" may be called a "part," "unit," "module," or "device."

[0022] A stitch pitch setting device (not shown) for setting a stitch pitch, which will be described later, may also be connected to the control device 100. The stitch pitch is set by the stitch pitch setting device in accordance with an input by a user through the display device 10. The set value of the stitch pitch may be configured to be stored in one area of ​​the storage device 102. This area itself may also be referred to as the pitch setting device.

[0023] The control device 100 cooperates with these devices to control the driving of the drive motor 2 and the oscillation motor 21. The storage device 102, the stitch pitch setting device, and the like can be configured as hardware modules in the control device 100, or can be provided as devices separate from the control device 100.

[0024] [First control mode] In the control mode of free motion stitching including the variable zigzag stitching described above, the control device 100 controls the drive motor 2 as shown in Fig. 5. First, the user places the workpiece at a predetermined position of the sewing machine 1, i.e., between the needle plate 5 and the presser foot 4 and directly below the needle 3 at the sewing start position, and then the user operates the speed controller 9 to determine the sewing speed Rset. The sewing speed Rset corresponding to the position of the speed controller 9 is stored in the memory device 102. At this time, the sewing machine 1 is still stopped.

[0025] When the start / stop key 8 is subsequently operated by the user, the sewing machine 1 switches to a standby state, and the movement detection device 7 starts to detect the movement of the sewing workpiece. Before the user starts to move the sewing workpiece, that is, while the movement detection device 7 does not detect the movement of the sewing workpiece, the drive motor 2 is stopped and the needle 3 does not move. Even if the user starts to move the sewing workpiece, the drive motor 2 remains stopped before the detection value by the movement detection device 7 exceeds a predetermined first threshold value Vh1 stored in the storage device 102. After this, when the detection value by the movement detection device 7 becomes equal to or greater than the first threshold value Vh1, the drive motor 2 is controlled based on the sewing speed Rset, and the sewing operation is automatically started. In this embodiment, the detection value by the movement detection device 7 corresponds to the movement speed V of the sewing workpiece calculated from the movement amount of the sewing workpiece per unit time obtained based on the output of the movement detection device 7. The sewing speed corresponds to the rotation speed of the drive motor 2. The detection value by the movement detection device 7 may be the movement amount of the sewing workpiece or the movement acceleration calculated from the movement amount.

[0026] For example, when sewing is completed and the movement of the sewing workpiece stops, the drive motor 2 is stopped when the value detected by the movement detector 7 falls below the first threshold value Vh1, the sewing operation is automatically stopped, and the sewing machine 1 goes into a standby state. Then, when the user operates the start-stop key 8 again, the standby state ends, the sewing machine 1 goes into a stopped state, and sewing is completed.

[0027] During sewing operation after the detection value by the movement detection device 7 becomes equal to or greater than the first threshold value Vh1, if the user operates the knee lifter 30 described above, a zigzag stitch is performed and the stitch width W of the zigzag stitch can be changed as appropriate.

[0028] That is, in the first control mode, when the rotation speed of the drive motor 2 is controlled based on the sewing speed Rset to perform free motion stitching, if the knee lifter 30 is operated, the control device 100 changes the drive amount of the amplitude motor 21 based on the operation amount of the knee lifter 30. In this way, a variable zigzag stitch is performed that can provide the stitch width W desired by the user.

[0029] In this variable zigzag stitch, if the sewing speed is too fast when the stitch width W is increased, the stitches may be disturbed. Therefore, in order to ensure sewing, the control device 100 may limit the sewing speed. For this purpose, an upper limit sewing speed Rlimit is stored in the storage device 102 in correspondence with the stitch width W, i.e., in correspondence with the drive amount of the amplitude motor 21 (or the operation amount of the knee lifter 30). The control device 100 compares the upper limit sewing speed Rlimit corresponding to the current drive amount of the amplitude motor 21 with the sewing speed Rset, and if the upper limit sewing speed Rlimit is lower, the control device 100 controls the drive motor 2 at the upper limit sewing speed Rlimit. In this control, the upper limit sewing speed Rlimit corresponds to the upper limit rotation speed of the drive motor 2.

[0030] In the above-described first control mode, the first threshold value Vh1 can be set to zero, but by applying a threshold value other than zero, a "play" is provided between the time when the user starts to move the sewing material and the time when the drive motor 2 starts to drive, i.e., the time when the needle 3 starts to move, and a safety margin is provided. Also, the first threshold value Vh1 may be configured so that the user can change the value through the operation device 101 or the display device 10.

[0031] [Example 1 of the first control mode] A first embodiment of the first control mode executed by the control device 100 in accordance with the program will be described with reference to the flowchart shown in FIG.

[0032] Start: The power to the sewing machine 1 is turned on, but before the user performs the operation to start free motion sewing, the sewing machine 1 is in a stopped state.

[0033] Next, the control device 100 monitors whether there is a driving start operation, such as when the start / stop key 8 of the operation device 101 is operated by the user (S601). The driving start operation of the operation device 101 may include, in addition to the operation of the start / stop key 8 for pushing a button, for example, detecting the depression of the foot controller 40 as a driving start operation. If there is no such driving start operation (No), the step of S601 is repeated.

[0034] When there is a driving start operation by the operation device 101 (Yes), the control device 100 starts detecting the movement of the workpiece by the movement detection device 7 and switches the sewing machine 1 to the standby state (S602). In this step of S602, although the sewing machine 1 can be started, the user has not yet moved the workpiece, and the drive motor 2 is stopped.

[0035] Next, the control device 100 monitors the movement of the workpiece by the movement detection device 7 (S603). If the movement of the workpiece is not detected by the movement detection device 7 (No), the control device 100 stops the drive motor 2 (S604). On the other hand, when the movement of the workpiece is detected by the movement detection device 7 because the user starts moving the workpiece (Yes), the control device 100 acquires the movement amount of the workpiece per unit time from the output of the movement detection device 7 and calculates the movement speed V of the workpiece based on this movement amount (S605).

[0036] Subsequently, the control device 100 compares the calculated movement speed V with the first threshold value Vh1 stored in the storage device 102 (S606). As a result of the comparison, if the movement speed V has not reached the first threshold value Vh1 (V < Vh1), the control device 100 stops the drive motor 2 (S604).

[0037] On the other hand, if the movement speed V has reached the first threshold value Vh1 or more (V ≧ Vh1), the control device 100 controls the rotation speed of the drive motor 2 based on the sewing speed Rset stored in the storage device 102 (S607). In this step, free motion sewing is executed, and variable zigzag sewing is also enabled.

[0038] After stopping the drive motor 2 in step S604, or after controlling the drive motor 2 at the sewing speed Rset in step S607, the control device 100 monitors whether or not the user has operated the operation device 101 to stop the operation (S608). The operation device 101 may, for example, operate the start / stop key 8 (pushing a button) or release the foot controller 40. If there has been no operation to stop the operation (No), the control device 100 repeats the process from S603 onwards. If there has been an operation to stop the operation (Yes), the control device 100 stops the drive motor 2 and also controls to end the standby state (S609).

[0039] [Second control mode] The control device 100 can also execute a second control mode for free motion sewing, which is different from the first control mode described above, and is configured to be able to switch between these modes in response to, for example, a user's input via the display device 10. In the first control mode according to the above-mentioned embodiment 1, the movement of the needle 3 is, so to speak, controlled at a constant speed, but in the second control mode described below, a (constant) stitch of a predetermined length can be obtained by controlling the drive motor 2 at a sewing speed Rverb proportional to a value detected by the movement detection device 7, which in this embodiment is the movement speed V of the sewing workpiece. This second control mode will be described with reference to FIG. 7.

[0040] The maximum sewing speed Rmax is determined according to the position of the speed controller 9, and when the start-stop key 8 is operated by the user, the movement detection device 7 starts detecting the movement of the workpiece. The sewing pitch desired by the user is set by the above-mentioned sewing pitch setting device. The maximum sewing speed Rmax is stored, for example, in one area of ​​the memory device 102, and this area may also be referred to as a maximum sewing speed setting device. In another embodiment, a maximum sewing speed setting device may be provided as a hardware module or a software module separately from the memory device 102.

[0041] When the user starts to move the sewing workpiece, the drive motor 2 is kept stopped before the value detected by the movement detection device 7, which in this embodiment is the movement speed V of the sewing workpiece, exceeds the second threshold value Vh2 stored in the memory device 102. When the movement speed V becomes equal to or greater than the second threshold value Vh2, the control device 100 starts driving the drive motor 2, and controls the drive motor 2 at a sewing speed Rverb proportional to the movement speed V so that sewing is performed at the set stitch pitch amount (proportional region in FIG. 7). In other words, the control device 100 calculates the sewing speed Rverb from the set stitch pitch amount and the movement speed V.

[0042] When the movement speed V of the sewing workpiece moved by the user further increases and reaches a third threshold value Vh3 stored in the memory device 102, the control device 100 controls the drive motor 2 at the maximum sewing speed Rmax. The maximum sewing speed Rmax at this time corresponds to the maximum value of the rotation speed of the drive motor 2.

[0043] The second threshold Vh2 in the second control mode is basically the same as the first threshold Vh1 in the first control mode (the first threshold Vh1 can be used as the second threshold Vh2), but the two can also be set to different values. The third threshold Vh3 is a value larger than the second threshold Vh2.

[0044] [Example 1 of the second control mode] A first embodiment of the second control mode executed by the control device 100 in accordance with the program will be described with reference to the flowchart shown in FIG.

[0045] After starting in the same manner as in Example 1 of the first control mode, steps S601 to S605, S608, and S609 denoted by the same reference characters as in Fig. 6 are the same as those in the first control mode of Example 1. Therefore, the following description will focus on steps S801 to S804, which are different.

[0046] After calculating the moving speed V of the workpiece to be sewn based on the moving amount of the workpiece to be sewn (S605), the control device 100 compares the moving speed V with a second threshold value Vh2 (S801). As a result of the comparison, if the moving speed V has not reached the second threshold value Vh2 (V < Vh2), the control device 100 stops the drive motor 2 (S604). On the other hand, if the moving speed V has reached the second threshold value Vh2 or more (V ≥ Vh2), the control device 100 compares the moving speed V with a third threshold value Vh3 (S802).

[0047] As a result of the comparison, if the moving speed V is equal to or less than the third threshold value Vh3 (V ≤ Vh3), the control device 100 controls the drive motor 2 at a sewing speed Rverb proportional to the moving speed V so that sewing is performed at the sewing pitch set by the sewing pitch setting device (S803). On the other hand, if the moving speed V exceeds the third threshold value Vh3 (V > Vh3), the control device 100 controls the drive motor 2 at the maximum sewing speed Rmax (S804). This maximum sewing speed Rmax is the upper limit speed of free motion sewing. For example, it may be stored in the storage device 102 in advance as the upper limit (response performance, etc.) rotational speed of the drive motor 2, or it may be the maximum rotational speed set in advance by the user in consideration of the user's skill, etc.

[0048] [Example 2 of the First Control Mode] Example 2 of the first control mode executed by the control device 100 according to the program will be described with reference to the flowchart shown in FIG. 9.

[0049] After starting in the same manner as in Example 1 of the first control mode, the steps S601 to S606 and S607 to S609 indicated by the same reference numerals as in Example 1 are the same as the control in Example 1. Therefore, Example 2 of the first control mode will be described centering on the steps S901 and S902 that are different from Example 1.

[0050] In this second embodiment, the memory device 102 stores a sewing start speed Rstart and an acceleration time T. When the moving speed V reaches or exceeds the first threshold value Vh1 (S606), the control device 100 controls the rotation speed of the drive motor 2 based on the sewing start speed Rstart stored in the memory device 102 and starts driving (S901). Next, the control device 100 increases the rotation speed of the drive motor 2 during the acceleration time T stored in the memory device 102, that is, performs acceleration control (S902). After the acceleration time T has elapsed, the control device 100 controls the rotation speed of the drive motor 2 based on the sewing speed Rset (S607). The needle 3 does not suddenly start moving at the sewing speed Rset, but the sewing speed gradually increases during the acceleration time T, so that the needle 3 starts moving slowly, providing a sense of security.

[0051] According to the embodiment described by exemplifying the above examples, the sewing machine 1 can switch between the first control mode and the second control mode according to the type of sewing, preference, etc., improving operability. In addition, the sewing machine 1 detects the start and stop of movement of the sewing workpiece by the user, and automatically controls the start and stop of the sewing operation in response to the start and stop, which is an advantage of improving operability. The timing at which the first control mode and the second control mode can be switched may be when the sewing machine is stopped (before an operation to start the operation) or when the sewing machine is on standby.

[0052] The present invention is not limited to the above-described embodiments, and various modifications are included in the present invention. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the configurations described. In addition, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. In addition, it is possible to delete a part of the configuration of each embodiment, or to add or replace another configuration.

[0053] The above-mentioned configurations, functions, processing units, processing means, etc. may be realized in part or in whole by hardware, for example, by designing them as integrated circuits. The above-mentioned configurations, functions, etc. may also be realized in software by a processor interpreting and executing a program that realizes each function. Information such as the program, table, file, etc. that realizes each function can be recorded in a recording device such as a memory, a hard disk (HDD) or a solid state drive (SSD), or a recording medium such as an IC card, an SD card, or a DVD.

[0054] The connection lines, control lines, information lines, etc. are those considered necessary for the explanation, and do not necessarily show all of the lines on the product. In reality, it can be considered that almost all components are connected to each other.

[0055] The above-described embodiment discloses at least the following aspects. [1] Sewing machine 1 is A movement detection device 7 that detects the amount of movement of the sewing workpiece; A drive motor 2 for operating the hands; A control device 100 that controls the driving of the drive motor 2; A storage device 102, The memory device 102 stores the sewing speed Rset and the sewing pitch. The control device 100 includes: a first control mode in which the drive motor 2 is controlled at the stored sewing speed Rset when the detection value by the movement detection device 7 exceeds a predetermined first threshold value Vh1; a second control mode in which, when a detection value by the movement detection device 7 exceeds a predetermined second threshold value Vh2, the drive motor 2 is controlled so that sewing is performed at a stored stitch pitch based on the detection value by the movement detection device 7; The control device 100 is switchable between the first control mode and the second control mode. [2] The first threshold value in the first control mode and the second threshold value in the second control mode are the same. [3] The sewing machine 1 further includes a needle left-right direction swinging mechanism 20, an amplitude motor 21 that drives the needle left-right direction swinging mechanism 20, and an operation device 101 that is operated by a user. The control device 100 controls the amplitude motor 21 based on the amount of operation of the operation device 101 . [4] The storage device 102 stores an upper limit sewing speed Rlimit based on the drive amount of the oscillation motor 21, When the upper limit sewing speed Rlimit is lower than the sewing speed Rset, the control device 100 controls the drive motor 2 at the upper limit sewing speed Rlimit. [5] The memory device 102 stores a sewing start speed Rstart and a predetermined acceleration time T. In the first control mode, when the detection value detected by the movement detection device 7 exceeds the first threshold value Vh1, the control device 100 starts controlling the drive motor 2 at the sewing start speed Rstart, and controls the drive motor 2 so that the sewing speed Rset reaches the stored sewing speed when the acceleration time T has elapsed. [6] A program executable by the control device 100 of the sewing machine 1 according to any one of [1] to [5] above, which, when executed by the control device 100, causes the control device 100 to execute the first control mode or the second control mode.

[0056] Although several embodiments of the present invention have been shown and described above, various other embodiments can be conceived based on the concept of the present invention understood from the above description. [Explanation of symbols]

[0057] 1. Sewing machine 2 Drive motor 3 needles 4 Press 5 Needle plate 6 Presser bar 7. Movement detection device 8 Start / Stop key 9 Speed ​​Controller 10 Display device 20 Needle left / right swing mechanism 21 Amplitude motor 22 Rotating shaft 23 Needle bar 30 Knee Lifter 31 Pad 32 Operation axis 33 Encoder 40 Foot Controller 41 Base 42 Treadboard 43 Encoder 100 Control device 101 Operating device 102 Storage device

Claims

1. A sewing machine, a movement detection device for detecting a movement amount of the sewing workpiece; A drive motor for operating the needle; A control device for controlling the driving of the drive motor; A storage device, The storage device stores a sewing speed and a sewing pitch, The control device includes: a first control mode in which the drive motor is controlled at the stored sewing speed when a value detected by the movement detection device exceeds a predetermined first threshold value; a second control mode in which, when a detection value by the movement detection device exceeds a predetermined second threshold value, the drive motor is controlled based on the detection value by the movement detection device so that sewing is performed at the stored stitch pitch, The control device is capable of switching between the first control mode and the second control mode.

2. The sewing machine of claim 1 , wherein the first threshold value and the second threshold value are the same.

3. The needle further includes a needle left-right direction swinging mechanism, an amplitude motor that drives the needle left-right direction swinging mechanism, and an operation device that is operated by a user. The sewing machine according to claim 1 or 2, wherein the control device controls the amplitude motor based on an amount of operation of the operating device.

4. the storage device stores an upper limit sewing speed based on a drive amount of the oscillation motor, The sewing machine according to claim 3 , wherein the control device controls the drive motor at the upper limit sewing speed when the upper limit sewing speed is lower than the sewing speed.

5. the storage device stores a sewing start speed and a predetermined acceleration time, 3. The sewing machine according to claim 1, wherein the control device, in the first control mode, when the detection value detected by the movement detection device exceeds the first threshold value, starts controlling the drive motor at the sewing start speed, and controls the drive motor to reach the stored sewing speed when the acceleration time has elapsed.

6. 3. A program executable by the control device of the sewing machine according to claim 1, the program causing the control device to execute the first control mode or the second control mode when executed by the control device.

Images