JP2009022574A - Control device of sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sewing machine being quickly stopped even during a sewing operation. <P>SOLUTION: The sewing machine 100 includes a first capacitive sensor 31 for detecting an approach of a hand Ha of an operator H to the upper face part 10 of a sewing machine bed part 2, and a control device 20 for controlling the actuation of a sewing machine motor 50, wherein the control device 20 stops the actuation of the sewing machine motor 50 when the first capacitive sensor 31 non-detects the approach of the hand Ha of the operator H during sewing. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sewing machine control device that controls operation and stop of a sewing machine.

  Conventionally, as a device for controlling a sewing machine so as not to perform an operation unintended by an operator in the sewing machine, a controller for switching start (ON) / stop (OFF) of the operation of the sewing machine and a power supply for switching on / off of power supply to the sewing machine A safety judgment device that judges whether the operation of the sewing machine is normal or abnormal according to the operation state of the controller when the power switch is turned on, a forced stop device that stops all operations of the sewing machine in the event of an abnormality, and power to the operator There is known a sewing machine including a safety display device that displays information for prompting re-insertion (for example, Patent Document 1).

In the sewing machine according to Patent Document 1, when the controller is in an operation state in which the operation of the sewing machine is started (ON) when the power switch is turned on by an operator's operation, the safety judging device determines that the sewing machine has been operated by an abnormal procedure. Then, all the operations of the sewing machine are stopped by the forced stop device. In addition, the controller instructs the controller to be turned on again after the controller is stopped (OFF) via the safety display device. Thereafter, when the power switch is turned on again while the controller is stopped (OFF), the sewing machine accepts subsequent operations by the controller.
JP-A-6-63269

  However, the conventional sewing machine control device including Patent Document 1 determines normality / abnormality of the procedure when the power switch of the sewing machine is turned on, and some abnormality occurred during the sewing operation by the sewing machine. The sewing machine motor stop control was not performed in accordance with various situations.

The operator has coped with the above-mentioned problems by switching the start / stop of the sewing machine by manually pressing the operation switch. However, when the operation switch is operated, the operator has to release his / her hand from the cloth, and sewing is continued until the sewing machine is stopped, and there is a problem that unintentional sewing is performed on the cloth. .
The operator also coped with the method by stopping the sewing machine by removing his foot from the stepping type controller. However, the operation of removing the foot from the controller has a problem that the operator may lose his posture.
In addition, any of the above-described methods has been insufficient as a countermeasure for unforeseen circumstances such as when the operator's hand is inadvertently positioned between the needle hole and the sewing needle.

  In view of the above-described problems, an object of the present invention is to provide a sewing machine that can urgently stop the sewing machine even during a sewing operation.

According to the first aspect of the present invention, there is provided a control device for a sewing machine in which an operator attaches a hand to a cloth and performs a sewing operation, the first electrostatic capacity sensor detecting the proximity of the operator's hand to the upper surface of the sewing machine bed, and the sewing machine. Drive control means for controlling the drive of the motor, wherein the drive control means stops the drive of the sewing machine motor when the first capacitance sensor does not detect the proximity of the operator's hand during sewing. It is characterized by.
Note that “a sewing machine in which an operator attaches a hand to a cloth and performs a sewing operation” refers to a sewing machine in which a cloth presser does not perform feed driving for moving a cloth, such as a main sewing machine.

The invention according to claim 2 is provided with a second capacitance sensor for detecting the proximity of the operator's hand to a predetermined range around the needle drop position of the needle plate in the sewing machine according to claim 1,
The drive control means is characterized in that the drive of the sewing machine motor is stopped or decelerated to a predetermined rotational speed when the second capacitance sensor detects the proximity of the operator's hand.

  According to a third aspect of the present invention, in the sewing machine according to the second aspect, the rotation speed of the sewing machine motor is stopped at a predetermined number of rotations when the second capacitance sensor detects the proximity of the operator's hand. Setting means for setting whether to decelerate is provided.

  According to a fourth aspect of the present invention, in the sewing machine according to the second or third aspect, when the proximity of the operator's hand is not detected by the first capacitive sensor, the first capacitive sensor is used by the operator. It is characterized by comprising first notifying means for notifying the operator that the proximity of the hand is not detected.

  According to a fifth aspect of the present invention, in the sewing machine according to any one of the second to fourth aspects, the proximity of the operator's hand is detected by the second capacitance sensor. A second notification means for notifying the operator that the proximity of the operator's hand has been detected by the capacitance sensor is provided.

According to the first aspect of the present invention, when the first capacitance sensor that detects the proximity of the operator's hand to the upper surface of the sewing machine bed does not detect the proximity of the operator's hand, the drive control means drives the sewing machine motor. Is stopped. Note that the stop state referred to here includes both the case where the stop state is maintained without starting sewing at the time of non-sewing and the case where the stop state is stopped at the time of sewing. At this time, the drive control means automatically stops the driving of the sewing machine motor. That is, the operator can stop the sewing machine simply by releasing his hand from the sewing product. As a result, when the operation switch of the sewing machine according to the prior art is operated, the operator must release his / her hand from the cloth, so that the sewing is continued until the sewing machine is stopped, and unintentional sewing is performed on the cloth. Can be solved. In addition, when the sewing machine is stopped by releasing the foot from the conventional stepping type controller of the sewing machine, it is possible to solve the problem that the operator may lose his / her posture due to the operation of releasing the foot from the controller. Therefore, the operator can use the sewing machine more comfortably, and the operability of the sewing machine is greatly improved.
Further, even when the operator does not operate the sewing machine and the switch or the controller for operating the sewing machine is not intended for some reason, the first electrostatic The sewing machine is not operated unless the capacitive sensor detects the proximity of the operator's hand to the top surface of the sewing machine bed. Therefore, it is possible to solve the problem that the sewing machine may be driven unnecessarily regardless of the operation of the operator, and the reliability of the sewing machine is greatly improved.
Further, since the electrostatic capacity sensor is used to detect the proximity of the operator's hand, the proximity of the operator's hand as a dielectric can be suitably detected, and the proximity of the cloth as an insulator is not detected. Therefore, the operator's hand, which may occur when using a mechanical switch that detects the presence or absence of an object by weight or pressing force, an optical switch that detects the presence or absence of an object by the presence or absence of light shielding, etc. It is possible to prevent erroneous detection due to the fact that the cloth cannot be distinguished. Therefore, the proximity of the operator's hand can be detected more suitably, and the reliability of the sewing machine is greatly improved.

According to the second aspect of the present invention, when the second capacitance sensor that detects the proximity of the operator's hand to the predetermined range around the needle drop position of the needle plate detects the proximity of the operator's hand, the drive control is performed. The means can stop the driving of the sewing machine motor. This makes it possible to stop the operation of the sewing machine when the operator's hand approaches the sewing needle that moves carelessly, and the reliability of the sewing machine is greatly improved.
Further, when the proximity of the operator's hand is detected by the second capacitance sensor that detects the proximity of the operator's hand to a predetermined range around the needle drop position of the needle plate, the drive control means drives the sewing machine motor. It is possible to decelerate. As a result, when the operator performs finer sewing, the operator can intentionally attach a hand near the needle entry position to operate the cloth and decelerate the sewing machine to perform finer and finer sewing. The operability of is greatly improved. Further, since the sewing speed is automatically reduced when the operator moves the hand around the needle drop position, it can be applied as a switch that intentionally reduces the sewing speed when performing fine sewing. Therefore, the sewing speed can be easily controlled, and the operability of the sewing machine is greatly improved.
Further, since the capacitive sensor is used to detect the proximity of the operator's hand as in the first aspect, the proximity of the operator's hand as the dielectric can be suitably detected, and the proximity of the cloth as the insulator can be detected. do not do. Therefore, the operator's hand, which may occur when using a mechanical switch that detects the presence or absence of an object by weight or pressing force, an optical switch that detects the presence or absence of an object by the presence or absence of light shielding, etc. It is possible to prevent erroneous detection due to the fact that the cloth cannot be distinguished. Therefore, the proximity of the operator's hand can be detected more suitably, and the reliability of the sewing machine is greatly improved.

  According to the invention described in claim 3, when the second capacitance sensor detects the proximity of the operator's hand by the setting means, it is set whether the rotational speed of the sewing machine motor is reduced to a predetermined rotational speed or stopped. It becomes possible. This makes it possible to select whether to perform the deceleration operation or stop the operation of the sewing machine when the operator's hand is positioned near the needle drop position. Therefore, when performing fine stitching, it is easy to perform sewing by setting the rotational speed of the sewing machine motor to be reduced to a predetermined number of rotations, otherwise it is inadvertently set to stop the sewing machine motor. It is possible to perform an emergency stop of the sewing machine when the operator's hand is positioned near the needle drop position. Therefore, a more flexible sewing machine operation is possible, and the operability of the sewing machine is greatly improved.

  According to the fourth aspect of the present invention, the first notification means notifies that the proximity of the operator's hand is not detected by the first capacitance sensor. Accordingly, when the sewing machine stops when the operator releases his / her hand from the upper surface of the sewing machine bed, that is, when the operator releases his / her hand from the cloth, the operator can know the reason why the sewing machine has stopped. Therefore, the operator can quickly move to an operation for resuming the operation of the sewing machine, that is, an operation of putting a hand on the cloth, and the operability of the sewing machine is greatly improved.

According to the fifth aspect of the present invention, the second notification means notifies that the proximity of the operator's hand has been detected by the second capacitance sensor. Accordingly, when the sewing machine is stopped or decelerated by unintentionally moving the hand near the needle drop position, it is possible for the operator to know the reason for the stop or deceleration. Therefore, the operator can move quickly so that the operation for returning the operation of the sewing machine to the normal state, that is, the operator's hand is not located near the needle drop position, and the operability of the sewing machine is greatly improved.
Further, when the operator's hand is intentionally positioned in the vicinity of the needle drop position when performing fine stitching or the like, it can be confirmed by the second notification means that the sewing machine has correctly detected the position of the operator's hand. . Therefore, the operator can easily confirm the operation of the sewing machine, and the operability of the sewing machine is greatly improved.

(Overall configuration of one embodiment of sewing machine of the present invention)
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The sewing machine 100 having the sewing machine control device 20 according to the present invention places a cloth on the upper surface of the sewing machine bed, and the operator H (see FIG. 7) presses the cloth K (see FIG. 7) with the hand Ha (see FIG. 7). A sewing machine that performs sewing by feeding (for example, a main sewing machine).
FIG. 1 is a block diagram showing a control device 20 of a sewing machine 100 according to the present invention and its peripheral devices. FIG. 2 is a side view of the sewing machine 100. FIG. 3 is a plan view showing the upper surface portion 10 of the sewing machine bed portion 2 of the sewing machine 100.

  As shown in FIG. 1 to FIG. 3, the sewing machine 100 has a control device 20 that controls various operations of the sewing machine 100, a first capacitance sensor detection unit 11, and a second capacitance sensor detection unit 12. A capacitance switch 30 that switches an output value according to whether or not proximity of the hand Ha of the operator H is detected, and a start / stop switch 41 that sets the start (ON) / stop (OFF) of the operation of the sewing machine 100 to be switchable. The sewing machine 100 is adjusted so that the sewing speed can be changed, and the sewing machine is stopped (OFF) / decelerated when the proximity of the hand Ha of the operator H to the second capacitance sensor detection unit 12 is detected. Based on the control of the control device 20, the needle vicinity operation setting switch 43 that sets the operation (LOW) to be switchable, the sewing machine motor 50 that rotates based on the control of the control device 20, and the control device 20. It includes a display device 60 for displaying, and Te.

  As shown in FIGS. 2 and 3, the sewing machine 100 includes a hole portion 13 provided on the upper surface portion 10 of the sewing machine bed portion 2 and provided with a needle hole through which the sewing needle 1a can pass, and the sewing machine arm portion 3. And a needle bar 1 that holds the sewing needle 1a and moves up and down with respect to the needle hole. Further, the upper surface portion 10 of the sewing machine bed portion 2 includes at least a first capacitance sensor detection unit 11 that detects the proximity of the hand Ha of the operator H over the entire upper surface portion 10 excluding the periphery of the hole portion 13; A second capacitance sensor detection unit 12 that detects the proximity of the hand Ha of the operator H around the hole 13 of the needle plate (not shown) is provided. The details of the first capacitance sensor detection unit 11 and the second capacitance sensor detection unit 12 will be described later.

  Although not shown, the sewing machine 100 is connected to at least the extending direction of the sewing machine arm portion 3 and rotates by driving the sewing machine motor 50, and the main shaft and the needle bar 1 are connected to rotate the main shaft. And a vertical movement mechanism that converts the movement into a vertical movement and transmits it to the needle bar 1. When the operator H operates the sewing machine 100 to operate, the sewing machine motor 50 is rotated by the control of the control unit 20. The rotation of the sewing machine motor 50 rotates the main shaft, and moves the needle bar 1 up and down via a vertical movement mechanism. In this way, a sewing operation by the sewing machine 100 is performed as is well known.

(Control devices and peripheral devices)
Next, the control device 20 of the sewing machine 100 and peripheral connection devices connected to the control device 20 will be described in detail.
As shown in FIG. 3, the control device 20 includes at least a CPU 21 that performs various arithmetic processes related to the control of the sewing machine 100, a ROM 22 that stores various programs and data related to the control of the sewing machine 100, and variables associated with the arithmetic processes of the CPU 21. 2, an EEPROM 24 that stores setting values set in the operator H in the control of the sewing machine 100, and an input / output interface 25 that can connect various related devices to the control device 20. Note that the EEPROM 24 is a rewritable nonvolatile storage device, and retains the stored contents even when the sewing machine 100 is turned off.

Further, the capacitance switch 30 is electrically connected to the input / output interface 25. The capacitance switch 30 includes at least a first capacitance sensor 31 that detects the proximity of the hand Ha of the operator H to the first capacitance sensor detection unit 11 described above, and the second capacitance sensor described above. The second electrostatic capacity sensor 32 that detects the proximity of the hand Ha of the operator H to the detection unit 12, and switches on and off based on the outputs of the first electrostatic capacity sensor 31 and the second electrostatic capacity sensor 32. And a capacitance detection circuit 33 that outputs to the control device 20. The capacitance detection circuit 33 is connected to the input / output interface 25 of the control device 20.
Details of the capacitance switch 30 will be described later.

  In addition to the capacitance switch 30, the input / output interface 25 includes at least a start / stop switch 41, a speed adjustment volume 42, a needle vicinity operation setting switch 43, a drive circuit 51 for driving the sewing machine motor 50, A display circuit 61 that outputs display contents to the display device 60 is electrically connected.

The sewing speed of the sewing machine 100 by the speed adjusting volume 42 is stopped in light of the rotational speed of the spindle (0 [rpm]), the minimum speed (50 [rpm]), the normal speed to the maximum speed (150 to 1500 [rpm]) ) Can be set. The normal speed to the maximum speed can be changed steplessly. Further, it is desirable that the speed adjustment volume is in a form that allows the operator H to perform an operation while putting the hand Ha on the cloth K (for example, a stepping controller).
Needless to say, the sewing speed of the sewing machine 100 by the speed adjustment volume described above is an example, and other numerical values may be used.

(Capacitance switch)
Next, the capacitance switch 30 will be described in detail.
FIG. 4 is a block diagram showing the configuration of the capacitance switch 30. FIG. 5 is an explanatory view showing each surface constituting the printed wiring board 10b. 5A shows the detection pattern surface 10bA, FIG. 5B shows the GND surface 10bB, FIG. 5C shows the first wiring surface 10bC, and FIG. 5D shows the second wiring surface 10bD. . FIG. 6 is an explanatory diagram for explaining the overlap and wiring of the surfaces constituting the printed wiring board 10b.

As shown in FIGS. 4, 5 (a), and 5 (d), the first capacitance sensor 31 covers the entire detection pattern surface 10 b </ i> A of the printed wiring board 10 b except for the periphery of the hole 13. The electrodes 31 a and 31 b wired in this manner, and the connector 31 c that connects the first capacitance sensor 31 and the capacitance detection circuit 33 are provided. The electrodes 31a and 31b are wired in parallel without contacting each other. That is, the electrodes 31a and 31b are wired so as to cover the first capacitance sensor detection unit 11 shown in FIGS. As shown in FIG. 5A, the electrodes 31a and 31b are wired so that the wirings are not in contact with each other, so that the electrodes 31a and 31b have a wide area as a single capacitance as in the first capacitance sensor detection unit 11. It becomes possible to cover with a sensor.
The second capacitance sensor 32 includes electrodes 32a and 32b wired so as to cover the periphery of the hole portion 13 of the printed wiring board 10b, the second capacitance sensor 32, and the capacitance detection circuit 33. And a connector 32c to be connected. The electrodes 32a and 32b are wired in parallel without contacting each other. That is, the electrodes 32a and 32b are wired so as to cover the second capacitance sensor detection unit 12 shown in FIGS. As shown in FIG. 5A, the electrodes 32a and 32b are provided with parallel lines in a spiral shape so that it can be suitably detected that the hand Ha of the operator H is close to the second capacitance sensor detection unit 12. Become.

  As shown in FIGS. 5 and 6, the printed wiring board 10b has a configuration in which the detection pattern surface 10bA, the GND surface 10bB, the first wiring surface 10bC, and the second wiring surface 10bD overlap. The detection pattern surface 10bA is a wiring board on which the electrodes 31a, 31b, 32a, and 32b are wired as described above. The GND surface 10bB is made of an insulator, and is provided so as not to cause a short circuit between the detection pattern surface 10bA and the first wiring surface 10bC. The first wiring surface 10bC and the second wiring surface 10bD are wiring boards that guide the ends of the electrodes 31a, 31b, 32a, and 32b to the connectors 31c and 32c, respectively. That is, the printed wiring board 10b is a so-called four-layer board. The connectors 31c and 32c are provided on the second wiring surface 10bD, and are electrically connected to the capacitance detection circuit 33 from a predetermined position on the bottom surface of the second wiring surface 10bD via a wiring (not shown). .

  Further, as shown in FIG. 4, an insulating plate 10a is provided on the upper surface of the printed wiring board 10b. The insulating plate 10a is made of a material (for example, acrylic, polyethylene terephthalate, etc.) that has a smooth upper surface and does not hinder the displacement of charges between the electrodes 31a, 31b, 32a, 32b of the capacitance sensors 31, 32. Become.

  The capacitance detection circuit 33 includes oscillators 33a and 33d that emit short-waves with a constant period, and an amplifier that amplifies the short-waves of the oscillator 33a and supplies the amplified short-waves to the electrode 31a via the connector 31c. 33b, the amplifier 33e that amplifies the short wave of the oscillator 33d and supplies the amplified short wave to the electrode 32a via the connector 32c, and the change in the capacitance of the first capacitance sensor 31 as a voltage. And a second detector 33f that detects the change in capacitance of the second capacitance sensor 32 as a voltage and outputs it to the control device 20. And comprising.

(Operation principle of capacitance switch)
Next, the operating principle of the capacitance switch 30 will be described in detail.
FIG. 7 is an explanatory view showing a case where the hand Ha of the operator H is located in the vicinity of the upper surface portion 10 of the sewing machine bed portion 2. FIG. 8 is a graph showing the relationship between the distance of the hand Ha of the operator H with respect to the upper surface portion 10 of the sewing machine bed portion 2 and the voltage value detected by the first detector 33c (second detector 33f).

  A short wave emitted from the oscillator 33a (33d) via the amplifier 33b (33e) is supplied to the electrode 31a (32a) of the capacitance sensor 31 (32). As a result, electric charge is stored in the capacitance sensor 31 (32). At this time, the amount of charge stored in the first capacitance sensor 31 (second capacitance sensor 32), that is, the capacitance is converted into a voltage value by the first detector 33c (second detector 33f). Detected. At this time, an electric field F is generated between the electrode 31a (32a) and the electrode 31b (32b).

  When the hand Ha of the operator H is in the vicinity of the first capacitance sensor detection unit 11 (second capacitance sensor detection unit 12) shown in FIGS. 1 and 2, the electrode 31a (32a) and the electrode 31b ( A part C of the electric charge of the electric field F during 32b) leaks through the hand Ha of the operator H. That is, part of the charge C stored in the capacitance sensor flows out as the body of the operator H becomes a dielectric. As a result, the capacitance of the capacitance sensor changes and is detected by the first detector 33c (second detector 33f) as a change in voltage value. A part C of the electric charge flowing out through the body of the operator H is stored as the electrostatic capacity of the operator H, and returns to the sewing machine 100 from a contact point with the sewing machine 100 other than the floor or the hand Ha.

That is, the proximity of the hand Ha of the operator H to the first capacitance sensor detection unit 11 (second capacitance sensor detection unit 12) provided on the upper surface portion 10 of the sewing machine bed unit 2 is the first static electricity. The displacement of the capacitance of the capacitance sensor 31 (second capacitance sensor 32) is detected by the first detector 33c (second detector 33f).
At this time, the displacement of the electrostatic capacitance, that is, the displacement of the voltage value detected by the first detector 33c (second detector 33f) is the upper surface portion 10 of the sewing machine bed portion 2 as shown in the graph of FIG. It has a predetermined relationship with the distance of the hand Ha of the operator H. That is, the proximity of the operator Ha's hand Ha to the upper surface 10 of the sewing machine bed 2 using the voltage value V1 when the hand Ha of the operator H approaches the upper surface 10 of the sewing machine bed 2 up to a predetermined distance L1 as a reference value. It is possible to determine whether or not there is any.
Needless to say, the voltage value V1 serving as the reference value can be adjusted by the settings of the capacitance detection circuit 33 and the control device 20.

  Note that the capacitance sensors used as the first capacitance sensor detection unit 11 and the second capacitance sensor detection unit 12 are known. By detecting the proximity of the operator Ha's hand Ha to the upper surface 10 of the sewing machine bed 2 by a capacitance sensor, the operator H's hand Ha approaches the upper surface 10 of the sewing machine bed 2 over the cloth K. Even if it exists, it becomes possible to detect the proximity of the hand Ha of the operator H suitably. In general, since the cloth K is an insulator that hardly displaces the electric potential of the electric field generated between the electrodes of the capacitance sensor, there is a risk of erroneous detection of the operator Ha's hand Ha and the cloth K as the sewing product. rare.

  The first detector 33c (second detector 33f) of the capacitance detection circuit 33 determines whether or not the hand Ha of the operator H is in proximity based on the above-described reference value, and the controller 20 detects the presence of the operator H. An output value indicating whether or not the hand Ha is close is output. The control device 20 determines whether or not the proximity of the hand Ha of the operator H by the first capacitance sensor 31 is detected based on the output of the first detector 33c, and based on the output of the second detector 33f. Whether the proximity of the hand Ha of the operator H is detected by the second capacitance sensor 32 is determined.

(Control of sewing machine operation by control device)
Next, operation control of the sewing machine 100 by the control device 20 will be described in detail.
When the start / stop switch 41 is ON, the control device 20 drives the sewing machine motor 50 according to the sewing speed indicated by the speed adjustment volume 42 to cause the sewing machine 100 to perform the sewing operation.
At this time, if the first capacitance sensor 31 of the capacitance switch 30 has not detected the proximity of the hand Ha of the operator H, the control device 20 controls the sewing machine 100 to stop. That is, when the hand Ha of the operator H is not located in the vicinity of the first capacitance sensor detection unit 11, the sewing machine 100 does not operate. Therefore, the control device 20 functions as “drive control means”.
At this time, the control device 20 causes the display device 60 to display a message indicating that the hand Ha of the operator H is not located on the upper surface portion 10 of the sewing machine bed portion 2. Therefore, the display device 60 functions as “first notification means”.

When the second capacitance sensor 32 of the capacitance switch 30 detects the proximity of the hand Ha of the operator H, the control device 20 operates the sewing machine 100 according to the setting of the needle proximity operation setting switch 43. When the setting of the needle vicinity operation setting switch 43 is OFF, when the second capacitance sensor 32 detects the proximity of the hand Ha of the operator H, the control device 20 controls to stop the sewing machine 100. When the setting of the needle vicinity operation setting switch 43 is LOW, the control device 20 operates the sewing machine 100 at the minimum speed regardless of the sewing speed indicated by the speed adjustment volume 42. That is, when the hand Ha of the operator H is located in the vicinity of the second capacitance sensor detection unit 12, the sewing machine 100 operates according to the setting of the needle vicinity operation setting switch 43. Therefore, the control device 20 functions as “drive control means”. The needle vicinity operation setting switch 43 functions as “setting means”.
At this time, the control device 20 causes the display device 60 to display a message indicating that the hand Ha of the operator H is located in the vicinity of the hole 13. Therefore, the display device 60 functions as “second notification means”.
Even if the second capacitance sensor 32 detects the proximity of the hand Ha of the operator H, the first capacitance sensor 31 does not detect the proximity of the hand Ha of the operator H. In that case, the control device 20 controls the sewing machine 100 to stop. That is, the sewing machine 100 does not operate.

That is, in the sewing machine 100, the start / stop switch 41 is ON, the hand Ha of the operator H is located in the vicinity of the first capacitance sensor detection unit 11, and the second capacitance sensor When the hand Ha of the operator H is not positioned in the vicinity of the detection unit 12, the control device 20 controls the sewing operation to be performed at the sewing speed indicated by the speed setting volume 42.
Further, when the start / stop switch 41 is OFF, the sewing machine 100 is controlled by the control device 20 so as not to operate.

  Various controls by the control device 20 are defined in a sewing program stored in the ROM 22 and executed by the CPU 21. The setting (OFF or LOW) by the needle vicinity operation setting switch 43 is stored in the EEPROM 24, and the previous setting is maintained even when the power is turned on again after the sewing machine 100 is turned off. It has become so.

(Machine operation)
Next, the operation of the sewing machine 100 will be described in detail according to the flowchart of FIG.
First, the control device 20 of the sewing machine 100 reads the setting of the start / stop switch 41 (step S1). At this time, when the start / stop switch 41 is OFF (step S2: NO), the control device 20 stops the sewing machine 100 (step S3).

When the start / stop switch 41 is ON (step S2: YES), the control device 20 reads the setting of the speed adjustment volume 42 (step S4). At this time, when the setting of the speed adjustment volume 42 is stopped (step S5: YES), the control device 20 returns to the process of step S1.
Otherwise (step S5: NO), the control device 20 reads the output value of the first detector 33c (step S6).

Next, the control device 20 determines whether the hand Ha of the operator H is in proximity to the first capacitance sensor detection unit 11 based on the output value of step S6 (step S7). When the proximity of the hand Ha of the operator H is not detected (step S7: NO), the control device 20 stops the sewing machine (step S8), and displays a message notifying the reason for the stop on the display device 60 (step S9). Note that the determination in step S7 may not be detected after a predetermined time has elapsed since the hand Ha is no longer detected. As a result, the motor stop control does not have to be performed until a hand is accidentally released during a normal sewing operation.
When the proximity of the hand Ha of the operator H is detected (step S7: YES), the control device 20 reads the output value of the second detector 33f (step S10).

Next, the control device 20 determines whether or not the hand Ha of the operator H is in proximity to the second capacitance sensor detection unit 12 based on the output value of step S10 (step S11). When the proximity of the hand Ha of the operator H is not detected (step S11: NO), the control device 20 controls the sewing machine motor 50 so that the sewing machine 100 operates at the sewing speed according to the setting of the speed adjustment volume 42 (step S12). . Thereafter, the control device 20 returns to the process of step S1.
When the proximity of the hand Ha of the operator H is detected (step S11: YES), the control device 20 reads the setting of the needle vicinity operation setting switch 43 (step S13). When the setting of the needle vicinity operation setting switch 43 is stopped (OFF) (step S14: OFF), the control device 20 stops the sewing machine (step S8), and displays a message notifying the reason for the stop on the display device 60 (step S14). S9). Thereafter, the control device 20 returns to the process of step S1.
When the setting of the needle vicinity operation setting switch 43 is decelerated (LOW) (step S14: LOW), the control device 20 controls the sewing machine motor 50 so that the sewing speed of the sewing machine 100 becomes the minimum speed (step S15). A message for informing the reason for operating at is displayed on the display device 60 (step S16). Thereafter, the control device 20 returns to the process of step S1.
Note that the determination in step S11 may be made when the hand Ha has been detected for a predetermined time or longer. As a result, it is not necessary to perform the motor stop control until a hand is accidentally swung near the needle hole for a moment in a normal sewing operation.

In the above-described processing, the settings and output values that are the branch conditions are read immediately before a branch occurs in the flowchart due to various settings and output values, but the settings and output values that are the branch conditions are read. May be any timing before branching occurs. For example, the control device 20 may first read and process all settings and output values.
Further, the display content of the message for notifying the reason for the stop performed in step S9 is performed for each cause of stop of the sewing machine 100. That is, when the sewing machine 100 stops because the proximity of the hand Ha of the operator H by the first detector 33c is not detected, for example, a message such as “No hand is attached to the cloth” is displayed. Further, when the sewing machine 100 stops because the proximity of the hand Ha of the operator H is detected by the second detector 33c, a message such as “the hand is too close to the needle hole” is displayed.

(Effects of the sewing machine according to the above embodiment)
According to the above-described embodiment, when the first capacitance sensor 31 does not detect the proximity of the hand Ha of the operator H to the first capacitance sensor detection unit 11, the control device 20 drives the sewing machine motor 50. Is automatically stopped. That is, the operator H can stop the sewing machine 100 only by releasing the hand Ha from the sewing product K. As a result, when the operation switch of the sewing machine according to the prior art is operated, the operator must release his / her hand from the cloth, so that the sewing is continued until the sewing machine is stopped, and unintentional sewing is performed on the cloth. Can be solved. In addition, when the sewing machine is stopped by releasing the foot from the conventional stepping type controller of the sewing machine, it is possible to solve the problem that the operator may lose his / her posture due to the operation of releasing the foot from the controller. Therefore, the operator H can use the sewing machine 100 more comfortably, and the operability of the sewing machine is greatly improved.
Further, even when the operator H is not operating the sewing machine 100 for any reason and the start / stop switch 41 and the speed adjustment volume 42 are set to operate the sewing machine, the first Unless the capacitance sensor 31 detects the proximity of the hand Ha of the operator H to the first capacitance sensor detection unit 11, the operation of the sewing machine 100 is not performed. Therefore, the problem that the sewing machine 100 may be driven unnecessarily regardless of whether or not the operator H is operating can be solved, and the reliability of the sewing machine is greatly improved.

When the setting of the needle vicinity operation setting switch 43 is stopped (OFF), the operation of the sewing machine 100 can be stopped when the hand Ha of the operator H is too close to the hole 13. As a result, when the hand Ha of the operator H comes close to the sewing needle 1a that moves inadvertently, the operation of the sewing machine can be stopped, and the reliability of the sewing machine is greatly improved.
Furthermore, when the setting of the needle vicinity operation setting switch 43 is set to deceleration (LOW), the operating speed of the sewing machine 100 can be set to the minimum speed when the hand Ha of the operator H comes close to the hole 13. Therefore, when the operator H performs finer sewing, the hand Ha is attached near the hole 13 and the cloth K is precisely operated, and the sewing machine 100 is decelerated, so that finer sewing can be performed more accurately. The operability of the sewing machine is greatly improved. In addition, when the operator H brings the hand Ha close to the second capacitance sensor detection unit 12, the sewing speed is automatically reduced. Therefore, it is applied as a switch for intentionally reducing the sewing speed when performing fine sewing. It becomes possible. Therefore, the sewing speed can be easily controlled, and the operability of the sewing machine is greatly improved.
Further, since the electrostatic capacity sensor is used to detect the proximity of the hand Ha of the operator H, the proximity of the hand Ha of the operator H as a dielectric can be suitably detected, and the proximity of the cloth K as an insulator is not detected. Therefore, the operator's hand, which may occur when using a mechanical switch that detects the presence or absence of an object by weight or pressing force, an optical switch that detects the presence or absence of an object by the presence or absence of light shielding, etc. It is possible to prevent erroneous detection due to the fact that the cloth K cannot be distinguished. Therefore, the proximity of the hand Ha of the operator H can be detected more suitably, and the reliability of the sewing machine is greatly improved.

  Furthermore, when the second capacitance sensor 32 detects the proximity of the operator's hand, the needle vicinity operation setting switch 43 can set whether to operate the sewing machine 100 at the minimum speed or to stop the sewing machine 100. Therefore, when performing fine stitching, the sewing machine 100 is set to operate at the minimum speed (LOW) so that sewing can be performed easily. Otherwise, it is careless to set the sewing machine 100 to stop (OFF). Thus, the sewing machine 100 can be urgently stopped when the hand Ha of the operator H is positioned near the needle drop position. Therefore, the sewing machine 100 can be operated more flexibly, and the operability of the sewing machine is greatly improved.

  Furthermore, the display device 60 notifies that the sewing machine 100 has stopped because the proximity of the operator's hand is not detected by the first capacitance sensor 31. Thus, when the operator H stops the hand 100 from the upper surface 10 of the sewing machine bed 2, that is, when the sewing machine 100 is stopped by releasing the hand from the cloth K, the operator H knows why the sewing machine 100 has stopped. Is possible. Therefore, the operator H can quickly move to the operation for resuming the operation of the sewing machine 100, that is, the operation of attaching the hand Ha to the cloth K, and the operability of the sewing machine is greatly improved.

Further, the display device 60 notifies that the sewing machine 100 has stopped or operated at the minimum speed because the proximity of the operator's hand has been detected by the second capacitance sensor 32. Accordingly, when the sewing machine 100 stops or operates at the minimum speed by unintentionally moving the hand Ha near the needle drop position, the operator H knows why the sewing machine 100 stopped or operated at the minimum speed. It becomes possible. Therefore, the operator H does not place an operation for returning the operation of the sewing machine 100 to the operation at the sewing speed by the setting of the speed adjustment volume 42, that is, the operator Ha's hand Ha is not positioned at the second capacitance sensor detection unit 12. The sewing machine can be moved quickly and the operability of the sewing machine is greatly improved.
Further, when the hand Ha of the operator H is intentionally positioned in the vicinity of the needle drop position when performing fine stitching or the like, the display device 60 indicates that the sewing machine 100 has correctly detected the position of the hand Ha of the operator H. Can be confirmed by. Therefore, the operator H can easily confirm the operation of the sewing machine 100, and the operability of the sewing machine is greatly improved.

(Other)
In the above-described embodiment, the operator H is notified by displaying a message on the display device 60. However, it is only necessary to notify the operator H of the operation status of the sewing machine 100, and the method is described above. It is not limited to the embodiment. For example, the notification may be performed by voice, or by turning on / off various lamps indicating the operation status of the sewing machine.
Further, although the control device 20 controls various operations of the sewing machine 100 by software processing, a similar function may be performed by a dedicated device or an analog circuit.

  Further, the arrangement positions and ranges of the first capacitance sensor detection unit 11 and the second capacitance sensor detection 12 are not limited to those described above, depending on the position of the needle hole, the area of the upper surface portion of the sewing machine bed portion, and the like. Needless to say, it may be changed to a suitable arrangement position and range.

In addition, the first capacitance sensor and the second capacitance sensor are not limited to two independent sensors, and a single capacitance sensor capable of detecting the proximity position is used to determine a predetermined range around the needle and It is good also as a structure which functions as a 1st electrostatic capacitance sensor and a 2nd electrostatic capacitance sensor by identifying with ranges other than.
Further, in that case, a new range around the needle as a second capacitance sensor is set, and the operator's hand approaches in the range around the needle as the second capacitance sensor. May be controlled to stop the sewing machine motor, and to decelerate the sewing machine motor to a predetermined speed when proximity of the operator's hand is detected in a new area outside the area around the needle. . In that case, by setting a new range, if the operator's hand is located in the range around the needle as the second capacitance sensor, a warning that the hand is too close to the needle hole In addition, when the operator wants to perform precise sewing, the operator is aware that the proximity of the operator's hand is detected in a new area outside the area around the needle. The resulting deceleration control of the sewing machine motor can be actively utilized.

It is a block diagram which shows the control apparatus of the sewing machine by this invention, and its peripheral connection apparatus. It is a side view of a sewing machine. It is a top view which shows the upper surface part of the sewing machine bed part of a sewing machine. It is a block diagram which shows the structure of an electrostatic capacitance switch. It is explanatory drawing which shows each surface which comprises a printed wiring board. 5A shows the detection pattern surface, FIG. 5B shows the GND surface, FIG. 5C shows the first wiring surface, and FIG. 5D shows the second wiring surface. It is explanatory drawing explaining the overlap and wiring of each surface which comprise a printed wiring board. It is explanatory drawing which shows the case where an operator's hand is located in the vicinity of the upper surface part of a sewing machine bed part. It is a graph which shows the relationship between the distance of the operator's hand with respect to the upper surface part of a sewing machine bed part, and the voltage value which a 1st detector (2nd detector) detects. It is a flowchart which shows the process in the actual operation | movement of a sewing machine.

Explanation of symbols

2 Sewing machine bed section 10 Upper surface section 11 First capacitance sensor detection section 12 Second capacitance sensor detection section 13 Needle hole 20 Control device 30 Capacitance switch 31 First capacitance sensor 32 Second Capacitance sensor 33 Capacitance detection circuit 50 Sewing motor 60 Display device

Claims (5)

A control device for a sewing machine in which an operator attaches a hand to a cloth and performs sewing work,
A first capacitance sensor for detecting the proximity of the operator's hand to the upper surface of the sewing bed;
Drive control means for controlling the drive of the sewing machine motor,
The sewing machine control device according to claim 1, wherein the drive control means stops driving the sewing machine motor when the first capacitance sensor does not detect the proximity of the operator's hand during sewing. A second capacitance sensor for detecting the proximity of the operator's hand to a predetermined range around the needle drop position of the needle plate;
2. The drive control unit according to claim 1, wherein when the second capacitance sensor detects the proximity of an operator's hand, the drive control unit stops driving or decelerates to a predetermined rotation speed. Sewing machine control device.   The setting means for setting whether to stop or decelerate the rotation speed of the sewing machine motor when the second capacitance sensor detects the proximity of the operator's hand. The sewing machine control device according to claim 2.   First notifying means for notifying the operator that the proximity of the operator's hand is not detected by the first capacitance sensor when the proximity of the operator's hand is not detected by the first capacitance sensor. The sewing machine control device according to claim 2, further comprising:   When the proximity of the operator's hand is detected by the second capacitance sensor, a second notification that informs the operator that the proximity of the operator's hand has been detected by the second capacitance sensor. The control device for a sewing machine according to any one of claims 2 to 4, further comprising a notification unit.

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