CN1699663B - sewing machine - Google Patents

Abstract

Sewing machine (1) of the present invention is arranged on the sewing machine main shaft (8) that is arranged in the arm portion (5) and is rotationally driven by the sewing machine motor; A power supply voltage control circuit that converts the generated power into a direct current of a specified voltage (for example, 5V), and is provided with a device that operates through the power supply, cumulatively calculates the cumulative running time T of the sewing machine 1, and prompts the time for maintenance (filling lubricating oil) Maintenance CPU (26).

Description

sewing machine

technical field

The present invention relates to a sewing machine in which a rotary shaft is rotationally driven or a drive shaft is reciprocally driven by a sewing machine motor. the

Background technique

Conventionally, in a sewing machine provided with a sewing mechanism including a needle bar, a thread hooking shuttle, etc., a commercial AC power supply is used as a driving power source for a sewing machine motor that drives the sewing mechanism. In addition, in an electronically controlled sewing machine provided with a control device including a CPU, in order to obtain a power source for driving the control device, a power source that converts the above-mentioned commercial power supply (for example, 100V alternating current) into a low-voltage direct current (for example, 5V direct current) is provided. device. the

However, there are various voltages (such as 100V, 200V, etc.) or methods (single-phase, three-phase) of commercial power supplies in some countries, and the types are different in each country. Therefore, in order to apply the control device to the various commercial power sources, a power supply device corresponding to each commercial power source is required. It is disadvantageous in terms of cost to prepare various power supply units in advance or to replace them. the

Therefore, in recent years, various sewing machines that use other power sources for the control of the sewing machine in addition to the above-mentioned commercial power source for driving the sewing machine motor have been proposed. the

For example, Japanese Patent No. 2941291 discloses a multi-power-driven sewing machine in which a solar battery is installed on a sewing machine frame. In this sewing machine, the power provided by the solar cell is stored in the storage battery inside the sewing machine. On the one hand, the sewing machine motor is driven by a commercial power supply. On the other hand, various stepping motors or pattern storage devices or pattern display devices are used. The structure of the low-voltage power supplied from the above-mentioned storage battery. the

However, such a sewing machine with a solar cell has a problem in that sunlight or a light source instead of sunlight is necessary for sewing, and the installation position of the sewing machine is limited. In addition, in order to save the driving power for driving various stepping motors, a large solar panel and storage battery are required, so there is a problem of high cost. the

In addition, for example, in an industrial sewing machine that only performs actual sewing, there is no control device for sewing machine control. For this type of sewing machine, it is best to remind the user to add grease to each part of the drive system (for oil) and other maintenance work. In order to prompt the time for this kind of maintenance, it is necessary to set up a CPU for maintenance, and through this CPU, the cumulative running time of each sewing time of the sewing operation is calculated while storing it, and when the predetermined time is reached A notification is given when the running time is accumulated. the

A storage battery (primary battery) can also be used as the power source of the CPU used to calculate the accumulated operating time, but the battery consumes a lot of power and has a short lifespan due to the need to continuously consume power to save the stored data. . In addition, in order to calculate the operation time, it is necessary to provide a rotation detection device such as an encoder or a rotation sensor to detect the rotation of the sewing machine main shaft, so the structure is more complicated, and expensive parts are added, resulting in an increase in cost. the

Contents of the invention

The object of the present invention is to provide a sewing machine which can realize the structure of obtaining auxiliary power in a simple and low-cost manner in a sewing machine which uses other power sources besides the commercial power source for driving the sewing machine motor. the

A first sewing machine according to the present invention is provided with a rotary shaft driven by a sewing machine motor, the sewing machine is provided with a generator that generates electricity through the rotation of the rotary shaft, and the power generated by the generator is converted into a power supply voltage of a predetermined voltage. A control circuit and electronics powered from said supply voltage control circuit. the

In the present invention, when the rotary shaft is rotationally driven by the sewing machine motor, the generator generates power, and the generated power is converted into a predetermined voltage by the power supply voltage control circuit and supplied to electronic devices. In this case, since a generator that generates electricity by rotation of the rotary shaft is used, unlike the case of using solar cells, the installation place of the sewing machine is not limited, and the sewing machine is small and inexpensive. In addition, no matter what kind of commercial power source the buyer uses to drive the sewing machine motor, the specified voltage for driving electronic devices can be obtained through the generator and the power supply voltage control circuit. the

Therefore, as a manufacturer, there is no need to prepare a variety of power supply units corresponding to various commercial power sources. Regardless of the country where the product is sold or the installation conditions, it can be solved with a single power supply unit (generator and power supply voltage control circuit). Furthermore, a structure for obtaining auxiliary power can be realized in a simple and low-cost manner. the

The above-mentioned electronic device includes a CPU mounted in the sewing machine body, and the power supply voltage control circuit has a constant voltage generating circuit for generating a power supply voltage of a prescribed voltage to be supplied to the above-mentioned CPU. The CPU can be operated using a power supply voltage of a predetermined voltage generated by the generator, and various electronic controls can be performed by the CPU. the

In this case, a configuration may be adopted in which a judging unit for judging the operation of the sewing machine is provided based on the voltage level of the power generated by the generator, and the CPU receives the output of the judging unit and calculates the accumulated operation time of the sewing machine. In this way, it is possible to perform maintenance management of the sewing machine, such as calculating the accumulated operation time of the operation of the sewing machine, and obtaining various maintenance periods using the accumulated operation time. Furthermore, since the generator can also be used as the rotation detecting device of the rotating shaft, the structure can be simplified. the

In addition, when the above-mentioned cumulative operation time reaches a predetermined value, there may be provided a prompting means for prompting this fact. Through the notification unit, it is possible to accurately notify that since the cumulative operating time has reached a predetermined value, it is time for maintenance such as adding lubricating oil (oil supply) to various parts of the drive system. the

At this time, a correction unit may be provided for changing the conversion ratio of the actual sewing time to the operation time calculated as the cumulative operation time according to the rotation speed of the rotary shaft. In this way, the calculated maintenance period is more accurate. the

In addition, a storage unit for storing the cumulative operating time calculated by the CPU and a reset switch for clearing the cumulative operating time stored in the storage unit may be provided. For example, at the end of maintenance, by operating the reset switch, the accumulated operating time stored in the storage unit can be cleared and initialized, so that the accumulated operating time can be repeatedly and effectively used. the

In this case, a battery may be provided that supplies power to the CPU when the reset switch is operated while the generator is not generating power. Therefore, even in a state where no power is generated by the generator, only the reset operation is performed and the CPU can be operated using the power of the battery. Since the power of the battery is only used for zeroing, the power consumption of the battery is very small, so it can work for a long time. the

The second sewing machine of the present invention is provided with a rotary shaft driven by the sewing machine motor, and this sewing machine is provided with a generator that generates electricity through the rotation of the rotary shaft, and a power supply voltage control that converts the generated power of the generator into a predetermined voltage. circuit and a power supply unit that supplies power generated by the power supply voltage control circuit to external electronic devices. the

No matter what kind of commercial power source the sewing machine motor is driven by, the specified voltage can be obtained from the power generated by the generator and supplied to external electronic devices. Therefore, as a manufacturer, it is not necessary to prepare various power supply devices corresponding to various commercial power supplies. Regardless of the country where the product is sold or the installation conditions, it can be realized with one power supply device (generator and power supply voltage control circuit), and the structure for obtaining auxiliary power can be realized in a simple and low-cost manner. the

In this case, the structure that can be adopted is: the sewing machine main body is provided with a charging part detachably mounted with external electronic components, and the power supply terminal of the charging part is powered by the above-mentioned power supply unit. Therefore, electronic devices that can only be used by charging can be charged. the

In the above-mentioned first or second sewing machine of the present invention, the generator may be constituted by a PM type stepping motor fitted externally on the rotary shaft. PM-type stepping motors are relatively inexpensive, durable, and smooth, so they are suitable for use. the

A third sewing machine of the present invention is provided with a drive shaft reciprocated by a sewing machine motor, this sewing machine is provided with a generator generating electricity through the reciprocating motion of the drive shaft, and a power supply voltage control unit that converts the generated power of the generator into a prescribed voltage circuits and electronic devices powered by said supply voltage control circuit. the

When the drive shaft is reciprocated by the sewing machine motor, the generator generates power, and the generated power is converted into a predetermined voltage by the power supply voltage control circuit and supplied to the electronic device. No matter what kind of commercial power supply the sewing machine motor is driven by, the specified voltage for driving electronic devices can be obtained through the power generated by the generator. Therefore, as a manufacturer, there is no need to prepare a variety of power supply units corresponding to various commercial power sources. Regardless of the country where the product is sold or the installation conditions, it can be realized with one power supply unit. Moreover, it can be realized with a simple and low-cost The way to achieve the structure of obtaining auxiliary power. the

Description of drawings

Fig. 1 is the front view of the sewing machine of the 1st embodiment of the present invention;

Fig. 2 is a longitudinal sectional front view of the base side part of the arm of the sewing machine;

Figure 3 shows the 4-phase AC waveform generated by the generator;

Figure 4 shows the rectified DC voltage waveform;

Fig. 5 is the circuit diagram showing electronic substrate circuit structure;

Fig. 6 is a flow chart showing the control steps of filling lubricating oil prompt;

Fig. 7 has shown the 2nd embodiment of the present invention, and it is equivalent to Fig. 5;

Figure 8 shows the relationship between the rotational speed stored in the EEPROM and the power generation voltage;

Figure 9 shows the relationship between the rotational speed and the correction coefficient stored in EEPROM;

Figure 10 is equivalent to Figure 6

Fig. 11 has shown the 3rd embodiment of the present invention, and it is the longitudinal sectional front view showing generator structure;

FIG. 12 shows a fourth embodiment of the present invention, which corresponds to FIG. 1 . the

Detailed ways

Example

Next, a first embodiment of the present invention will be described with reference to FIGS. 1 to 6 . the

Fig. 1 shows the overall structure of a sewing machine 1 of this embodiment. Described sewing machine 1 is provided with horizontal base 3, and the pin post 4 erected upwards from this base 3 right-hand side, and the arm portion 5 that extends leftward from this pin post 4 upper end, and is placed on the console 2. the

An unillustrated thread wheel catcher is provided in the base 2, and a thread gripper 6 is provided in the front portion of the arm portion 5. Inside the arm portion 5, a sewing machine main shaft 8 (shown only in FIG. 2 ) extending in the left-right direction as a rotation shaft is freely rotatably provided. In addition, a needle bar drive mechanism and a thread take-up drive mechanism (not shown) are provided inside the arm portion 5 . the

The above-mentioned needle bar drive mechanism is used to convert the rotational drive of the sewing machine main shaft 8 into the vertical drive of the needle bar 9 provided at the lower portion of the front end of the arm portion 5 . A sewing needle 10 is installed at the lower end of the needle bar 9 . The above-mentioned thread take-up drive mechanism is used to convert the rotational drive of the sewing machine main shaft 8 into the vertical drive of the thread take-up (not shown). In addition, the rotational driving force of the sewing machine main shaft 8 is also transmitted to the above-mentioned thread wheel catcher, and the thread wheel catcher is driven synchronously with the vertical movement of the needle bar 9 . Like this, constituted sewing mechanism. the

In addition, a back-tack control lever 11 for back-tacking is provided in the above-mentioned foot column 4 . An upper portion of the arm portion 5 is provided with a bobbin thread winding device 13 . In addition, a green light 54 and a red light 56 to be described later are provided on the front surface of the arm portion 5 . the

In addition, although not shown in the figure, a sewing machine motor constituting a driving source of the sewing machine main shaft 8 is provided in the above-mentioned console 2, and a pedal-type start/stop switch and the like are also provided. As shown in the partial schematic view of Fig. 2, a pulley is fixed on the output shaft of the sewing machine motor, and a V-belt 7 is wound between the pulley and the pulley 18 fixed on the right end of the sewing machine main shaft 8. In this way, the sewing machine main shaft 8 can be rotationally driven by the sewing machine motor. In addition, the above-mentioned sewing machine motor is driven by the electric power supply of the commercial power supply. In this case, a motor suitable for the type (voltage and power supply method) of the commercial power supply receiving the electric power supply should be used. the

In the sewing machine 1 of the present embodiment, the generator 15 is mounted externally on the sewing machine main shaft 8 . Moreover, a power supply voltage control circuit for converting the electric power generated by the above-mentioned generator 15 into direct current of a predetermined voltage (for example, 5V) is provided, and at the same time, a CPU 26 for maintenance of electronic devices operated by power supply through the power supply voltage control circuit is provided. . the

Next, the generator 15 will be described. As shown in FIG. 2 , the sewing machine main shaft 8 is rotatably supported by the sewing machine frame 12 via bearings 16 and 17 at the right end portion inside the arm portion 5 . In the present embodiment, the generator 15 is constituted by a PM type (permanent magnet type) stepping motor, and is installed between the above-mentioned bearings 16 and 17 . Since the technique of using such a PM type stepping motor as the generator 15 to generate electricity is well known, it will only be briefly described. the

That is, the sleeve 20 is fitted and fixed to the outer periphery of the sewing machine main shaft 8 . On the outer periphery of the sleeve 20, for example, a 24-pole magnet group 21 in which 12 S poles and 12 N poles are arranged in a circle along the circumferential direction is provided. the

On the other hand, in the above-mentioned sewing machine frame 12 , on the side of the bearing 16 , a ring-shaped bracket member 19 made of aluminum is fastened by screws at a plurality of places, and a cover 22 is attached to the bracket member 19 . Four-phase coils 23a to 23d wound on two bobbins (creels) arranged in the axial direction shown in FIG. 5 are housed in the housing 22 . These coils 23 a - 23 d are disposed opposite to the outer periphery of the ring magnet group 21 and maintain a small gap with the outer periphery of the ring magnet group 21 . Although not shown in the drawings, the coils 23a, 23c are wound on one bobbin in a state in which the winding directions are opposite to each other and connected in series. The coils 23b and 23d are wound on the other bobbin in a state in which the winding directions are opposite to each other and connected in series. In each bobbin, a tooth sensor (not shown) is provided on the inner periphery of the coils 23a to 23d. the

In this way, the rotation of the sewing machine main shaft 8 drives the ring magnet group 21 to rotate, and a magnetic field is generated in each of the coils 23a-23d in the generator (PM type stepping motor) 15, thereby generating a waveform by the phase angle as shown in FIG. 3 . AC voltage composed of 4 phases of Φ1 to Φ4 with a difference of 90 degrees. At this time, the frequency of the generated AC voltage is proportional to the number of revolutions of the main shaft 8 of the sewing machine. As shown in FIG. 5, the generator 15 is provided with four output terminals and a ground terminal from each coil 23a-23d. In the ground terminal, the connection point of the coils 23a, 23c and the connection point of the coils 23b, 23d are connected. the

The power supply voltage control circuit and the CPU 26 for maintenance are mounted on an electronic board 25 (see FIG. 5 ). Next, the power supply voltage control circuit and the CPU 26 for maintenance will be described with reference to FIG. 5 . In addition, although not shown in the drawings, an electronic substrate 25 is housed in a case to form an assembly and is provided behind the above-mentioned arm portion 5 . At this time, a rear cover is provided in an openable and closable manner at the rear of the box, and a reset switch 45 and an alarm buzzer 50 described later are provided on the rear cover part. the

First, as shown in FIG. 5, the maintenance CPU 26 is composed of a single-chip microcomputer. The CPU 26 for maintenance includes an EEPROM (ROM capable of electronically writing and erasing data) 26a, a RAM 26b, a plurality of input ports I1-I8, output ports O1-O3, and the like. The above-mentioned EEPROM 26a is used as a storage unit for storing the accumulated operation time of the sewing machine 1 . the

The structure of the above power supply voltage control circuit is shown in FIG. 5 . The numbered and unnumbered small rectangular boxes in the figure represent resistors. the

The output terminal of the generator 15 described above is connected to a connector 25a provided in the electronic board 25. At this time, the four-phase (Φ1-Φ4) outputs from the four coils 23a-23d of the generator 15 are half-wave rectified by diodes D1-D4, respectively, and supplied to the power supply line L1. The DC waveform including pulsating components after such half-wave rectification is shown in Figure 4. In addition, the ground terminal of the generator 15 is connected to the ground line GL1. the

A Zener diode (voltage stabilization element) 27 is connected between the power supply line L1 and the ground line GL1 , and the Zener diode (voltage stabilization element) 27 is connected to a base of a transistor 28 . The Zener diode 27 is used to limit the voltage to 10V, and the Zener voltage is set to about 10V, for example. the

When the transistor 28 starts to operate by applying a Zener voltage, the direct current flowing through the transistor 28 is limited by the next current-limiting transistor 29 and input to the backflow preventing diode 30 . In the 10V line L2, the current flowing through the backflow prevention diode 30 is smoothed by the capacitor group 31A. The smoothed direct current with a voltage of about 10 V is supplied to the next Zener diode 32 and simultaneously supplied to the 3-terminal regulator 33 . The further smoothed DC current obtained by the 3-terminal regulator 33 and the capacitor bank 31B is supplied to the common 5V line L5 through the first stabilized voltage line L3. the

On the other hand, the Zener diode 32 connected between the above-mentioned 10V line L2 and the ground line GL2 is used to limit the voltage of 5V, and the Zener voltage is set to about 5V, for example. The direct current flowing through the transistor 34 operated by applying the Zener voltage of the Zener diode 32 charges the large-capacity capacitor 36 after passing through the diode 35 and the resistor 60 provided in the second constant voltage line L4. At the same time, it is supplied to the general-purpose 5V line L5 through the diode 37, and the general-purpose 5V line L5 is connected to the power supply terminal 14 (VCC terminal) of the CPU 26 . the

That is, a 5V direct current is supplied to the common 5V line L5 via the first stabilizing line L3, and a 5V direct current is supplied to the common 5V line L5 via the second stabilizing line L4. When the sewing machine main shaft 8 rotates and a voltage is generated in the generator 15, the first voltage stabilizing line L3 is preferentially used. Here, the ground line GL2 is connected to the ground terminal 15 (GND terminal) of the CPU 26 . the

The power supply line L1 is connected to one input terminal of the comparator 38 through a resistor 61 . At the same time, a capacitor 39 , a resistor 40 , and a Zener diode 41 are connected in parallel to the resistor 61 in series. The Zener voltage of the Zener diode 41 is set to 9 V, for example, and a voltage of about 9 V limited by the Zener diode 41 is applied to the above-mentioned one input terminal of the comparator 38 . The voltage of about 0.5 V obtained by dividing the 5 V output of the three-terminal regulator 33 by two voltage dividing resistors 42 and 43 is applied to the other input terminal of the comparator 38 as a standard voltage. the

Thus, if the DC voltage applied to one input terminal of the comparator 38 is smaller than the standard voltage applied to the other input terminal, "0V" voltage is supplied to the input terminal I1 of the CPU 26 through the generated voltage supply line L6. If the DC voltage applied to one input terminal is larger than the standard voltage applied to the other input terminal, "5V" DC power is supplied to the input terminal I1 through the generation voltage supply line L6. the

At this time, when the rotation speed of the sewing machine main shaft 8 reaches about 200-250rpm, a direct current of about 1V or more is applied to the power supply line L1, and about 5V, that is, an "H" level generated voltage signal, is supplied to the input terminal I1. In the reset voltage supply line L7 connected between the ground line GL2 and the common 5V line L5, a primary battery 44 made of a lithium battery or the like, a first switch 45a of the reset switch 45, and a backflow preventing diode 46 are respectively provided. the

The second switch 45b of the reset switch 45 is interposed between the ground line GL2 and the clear terminal I6 of the CPU 26 . Here, these 1st switch 45a and 2nd switch 45b perform ON operation simultaneously with manual operation of an operation button. Here, an operation button of the reset switch 45 is fitted inside a hole provided in the rear cover. The user can press the operation button only by using the elongated rod. the

The alarm buzzer 50 and its driving circuit 51 are connected to the output terminal O1. The alarm buzzer 50 is connected to the first voltage stabilizing line L3 through a diode 52 . The green lamp 54 and its driving circuit 55 are connected to the output terminal O2. The green light 54 is connected to the first voltage stabilizing line L3 through a diode 52 . Furthermore, a red lamp 56 and its drive circuit 57 are connected to the output terminal O3. The red light 56 is connected to the first voltage stabilizing line L3 through a diode 52 . the

Here, the green light 54 is used to prompt the normal state that the drive system of the sewing machine 1 is working normally. In addition, as described later, since the sewing machine 1 has been running for a specified time (for example, about 700 hours), the red light 56 can urge the filling of lubricating oil (butter) in the multiple drive shafts of the sewing machine 1, that is, a reminder The function of the warning light that the sewing machine is in the maintenance period. the

A crystal oscillator 58 is connected to the input terminals I2 and I3 of the CPU 26 described above. Moreover, the output terminal of the reset element 59 is connected to the input terminal (insertion terminal) I8, and the input terminal of the reset element 59 is connected to the common 5V line L5. In this way, when the sewing machine main shaft 8 is not running and the DC voltages of the first voltage stabilizing line L3 and the second voltage stabilizing line L4 both drop to about 2.8V, the reset signal generated by the reset element 59 is provided to the input terminal I8. When the CPU 26 for maintenance receives this reset signal, it masks the interrupt and forcibly saves the cumulative operating time T described later in the cumulative memory of the EEPROM 26a. the

Here, the power supply voltage control circuit consists of a power supply line L1, a 10V line L2, a first voltage stabilization line L3, a second voltage stabilization line L4, a common 5V line L5, Zener diodes 27, 32, transistors 28, 29, 34, Capacitors 31A, 31B, and 36, diodes D1 to D4, 30, 35, and 37 are formed. Among them, through the 10V line L2, the first stabilized voltage line L3, the second stabilized voltage line L4, the common 5V line L5, Zener diodes 27, 32, transistors 28, 29, 34, capacitors 31A, 31B, diodes 30, 35, 37 and the like form a voltage stabilizing generating circuit. the

In addition, the comparator 38, the resistor 61, the capacitor 39, the resistor 40, the Zener diode 41, the voltage dividing resistors 42, 43 and the like constitute a judging unit for judging whether the sewing machine 1 is in operation. The red light 56, the alarm buzzer 50 and the like constitute a prompting unit for prompting that the accumulated running time of the sewing machine has reached a predetermined value. the

Next, the operation of the above configuration will be described with reference to the flowchart of FIG. 6 . In the EEPROM26a of the above-mentioned CPU26, the control program of the lubricating oil filling prompt is stored in advance. By executing this control program, the CPU 26 performs the processing shown in FIG. 6 . Symbol Si (i=11, 12, 13 . . . ) in FIG. 6 denotes a step. In addition, when this sewing machine 1 is shipped, the data of the cumulative operating time T stored in the cumulative memory of the EEPROM 26a is cleared to zero. the

When sewing, if the user depresses the start/stop switch (pedal), the motor of the sewing machine will run, the V-belt 7 will drive the sewing machine main shaft 8 to rotate, and the sewing device will perform the sewing operation. At this time, by the rotation of the sewing machine main shaft 8, the generator 15 operates to generate a four-phase AC voltage (Φ1 to Φ4). In this case, since the large-capacity capacitor 36 has not been charged at first, the power supply voltage has not been supplied to the input terminal I4 of the CPU 26 from the general-purpose 5V line L5 via the second constant voltage line L4. the

Since the AC voltage from the generator 15 is half-wave rectified by the diodes D1 to D4 and supplied to the power supply line L1, if the DC voltage supplied to one input terminal of the comparator 38 through the power supply line L1 is higher than When the standard voltage (about 0.5V) of the other input terminal is high, that is, when the rotation speed of the sewing machine main shaft 8 is higher than about 200-250rpm, then the comparator 38 provides an "H" level generated voltage signal to the input terminal I1. the

At this time, the generated voltage signal Gv applied to the input terminal I1 is read (S11), and if the generated voltage signal Gv is "H" level (S12: Yes), the green lamp 54 is turned on (S13). Afterwards, when the generated voltage signal Gv read at very short intervals is at the "H" level, that is to say, when sewing (S15, S16: Yes), the running time t of the sewing machine 1 during this sewing Calculations are performed (S14). the

Next, when the generated voltage signal Gv becomes "L" level and the sewing machine 1 stops running (S16: No), the green light 54 goes out (S17), and the current running time t is added to the accumulated running time T of the last time. The latest cumulative running time T (S18). Thereafter, the latest cumulative operating time T is stored in the cumulative memory of the EEPROM 26a (S19). Next, if the accumulated operating time T is less than the predetermined set time B (for example, about 700 hours) (S20: No), steps S11 to S20 are repeated. the

On the contrary, if the accumulated operation time T is equal to the set time B (S20: Yes), then the red lamp 56 is lit, and the alarm buzzer 50 is activated simultaneously (S21). Through the alarm buzzer 50 and the red light 56, the user is notified that the maintenance period (lubricating oil filling) has arrived. After receiving this information, the user can carry out the maintenance work of adding butter or lubricating oil to the specified drive system at an appropriate time. the

When the user finishes adding butter, he presses and operates the above-mentioned reset switch 45 (S22: Yes). Thus, a clearing process (S23) of writing an initial value "0" in the accumulated operation time T stored in the accumulated memory is performed. Afterwards, the sewing machine 1 can continue to perform normal sewing operations. the

However, when the reset switch 45 is pressed, the direct current supplied from the primary battery 44 is supplied to the common 5V line L5 through the closed first switch 45a and the backflow preventing diode 46 . At the same time, since the input terminal (clear terminal) I6 is grounded by the closed second switch 45b, the accumulated operating time T stored in the accumulated memory is cleared according to the "L" level clear signal. At this time, since the primary battery 44 (lithium battery) is only used to clear the accumulated running time T, its lifespan is very long, for example, it can be used for about 7 to 10 years. the

The following effects can be obtained by using this embodiment. In this embodiment, a generator 15 is provided to generate power by rotating the sewing machine main shaft 8, and the power supply voltage control circuit converts the generated power into DC power of a predetermined voltage to obtain power for driving the maintenance CPU 26. Therefore, it is different from the conventional device that stores the power provided by the solar cell into the storage battery to obtain the driving power of the control device, so there is no restriction on the place where the sewing machine 1 is placed, and it is small in size and cheap in price. the

Moreover, it is different from a device that is provided with a power supply unit that converts a commercial power supply into a direct current of a specified voltage to supply to the CPU. Even if the buyer of the sewing machine 1 uses any commercial power supply to drive the sewing machine motor, the generator 15 and the power supply voltage can be used to drive the sewing machine motor. The control circuit obtains a predetermined voltage for driving the CPU 26 for maintenance. Therefore, as a manufacturer, it is not necessary to prepare various power supply devices corresponding to various commercial power supplies. Regardless of which country the product is sold to or what the installation conditions are, it can be solved by a generator 15 and a power supply voltage control circuit, and an auxiliary power supply structure can be obtained in a simple and cheap manner. the

In the present embodiment, as an electronic device, since a maintenance CPU 26 is provided to calculate and store the cumulative operation time T of the sewing machine to obtain the maintenance period (time for filling lubricating oil), the sewing machine 1 can be appropriately maintained and managed. . At this time, the generator 15 can also be used as the rotation detection device of the sewing machine main shaft 8, therefore, it is not necessary to arrange other electronic components such as an encoding device, so the structure is simpler and cost saving. the

In addition, when the cumulative running time T stored in the cumulative memory of EEPROM26a reaches the set time B, since the red light 56 and the alarm buzzer 50 can prompt the situation visually and audibly, the user can be clearly reminded that the sewing machine has arrived for maintenance. Expect. The generator 15 adopts a PM type stepping motor, so it has the advantages of low cost, good durability and good smoothness. the

Several variations of the present invention are described below. Following variation is to have carried out partial change on the basis of above-mentioned 1st embodiment. Therefore, the same reference numerals are used for the same parts as those of the above-mentioned first embodiment, so new illustrations and detailed descriptions are omitted, and only the differences from the first embodiment will be described. the

1) Figures 7 to 10 show the second embodiment of the present invention. In this second embodiment, the circuit of the electronic board 25A is partially changed from that shown in FIG. 5 . That is, as shown in FIG. 7 , the comparator 38 is not provided on the generated voltage supply line L6 , and the direct current of the power supply line L1 is still supplied to the input terminal I1 . Along with this, an A/D converter (analog/digital converter) 26 c is added to the CPU 26 . At this time, for example, the Zener voltage of the Zener diode 41A is set to 5V, and the upper limit of the DC voltage is limited to about 20V. the

In addition, in EEPROM 26a, as shown in FIG. 8, a tachometer corresponding to the generated voltage (V) and the rotational speed (rpm) is stored. At the same time, as shown in FIG. 9 , a correction coefficient table corresponding to the rotational speed (rpm) and the correction coefficient is stored. Here, when the rotation speed of the sewing machine main shaft 8 is 3000 (rpm), the sewing time is also applied to the running time. In contrast, when the rotational speed of the sewing machine main shaft 8 is lower than the aforementioned rotational speed, the conversion ratio of the actual sewing time to the operating time is reduced. In order to carry out the conversion, a correction factor should be set in advance. the

That is, as shown in the flowchart of FIG. 10, the generated voltage (V) applied to the input terminal I1 is read (S31), and the rotation speed V is calculated from the tachometer shown in FIG. The correction coefficient table shown in FIG. 9 calculates the correction coefficient (S32). Afterwards, when the rotating speed V is higher than the predetermined set rotating speed Va (for example, about 300rpm) (S33: Yes), the green light 54 is lit (S34), and at the same time, calculate the predetermined running time t (for example, about 1 second) ( S35), based on the correction coefficient obtained in step S32, calculate the corrected operating time Htn (S36). the

Next, the generated voltage is read (S37), and the rotational speed V and the correction coefficient are respectively calculated (S38) as in step S32. When the rotational speed V is higher than the set rotational speed Va (S39: Yes), steps S34 to S39 are repeatedly executed. With the completion of the sewing operation, when the rotation speed V is lower than the set rotation speed Va (S39: No), the green lamp 54 is turned off (S40). the

Thereafter, the current total operating time Ta obtained by adding all the corrected operating times Ht1, Ht2, Ht3, . . . Htn formed by the current sewing operation system is calculated (S41). Then, the latest cumulative operating time T obtained by adding the current total operating time Ta to the previous cumulative operating time T is calculated (S42). Thereafter, steps S43 to S47 are executed in the same manner as above-mentioned steps S19 to S23. Therefore, in this case, it is possible to more accurately calculate the cumulative operating time T corrected according to the rotation speed of the sewing machine main shaft 8 as the time corresponding to lubricating oiling. Here, the A/D converter 26c, steps S31 to S33 of the lubricating oil presentation control and the like constitute the judging means.

2) Fig. 11 shows the third embodiment of the present invention. In the third embodiment, the generator 15A is constituted by a so-called linear motor that generates electricity by the up and down movement of the needle bar 9, which is a drive shaft reciprocated up and down by the sewing machine motor. The needle bar 9 is supported on the sewing machine frame 12 through a pair of upper and lower bearings 65, 66 so as to be reciprocable up and down. the

The structure of the generator 15A is as follows. That is, a fixedly mounted fixing fitting 67 is fixed on the needle bar 9 , and the magnet bracket 68 is supported vertically by the fixing fitting 67 . A 16-pole magnet group 70 is provided on the magnet bracket 68 , and in this magnet group, for example, eight S poles and eight N poles are arranged linearly with each other in the vertical direction. The four coils 23a to 23d are dispersed in a pair of upper and lower core frames 71 and 72 formed in a substantially U-shape very close to the right side of the linear magnet group 70 . A gap is provided between the core frames 71 and 72, and its size corresponds to 1/4 of the length λ of the magnet pair composed of the N-pole magnet and the S-pole magnet. the

In this structure, since the needle bar 9 reciprocates up and down due to the driving of the sewing machine motor, and at the same time, the magnet bracket 68 also moves up and down within a predetermined distance, therefore, a moving magnetic field is generated in each of the coils 23a to 23d, thereby generating a magnetic field. An AC voltage composed of four phases whose phase angles differ by 90 degrees. The electric power generated by the vertical reciprocating motion of the needle bar 9 is converted into DC power of eg 5V by the power supply voltage control circuit and supplied to the CPU 26 for maintenance by the generator 15A. The same effect as that of the above-mentioned first embodiment can also be obtained by the second embodiment. the

3) Fig. 12 shows the fourth embodiment of the present invention. In this embodiment, the electric power obtained by the generators 15, 15A is not supplied to the CPU 26 for maintenance built in the sewing machine 1, but is used for external electronic devices such as mobile phones, MD players or CD players, digital Power supply (charge) to the camera, etc. the

At this time, in the sewing machine 1A, for example, on the front surface of the leg 4, there is provided a vertical mounting recess 4a as a charging portion for detachable mounting of various electronic components. A pair of power supply terminals 4b are provided in the mounting recess 4a. Electric power generated by generators 15 and 15A is converted into predetermined DC power by a power supply voltage control circuit, and supplied to a pair of power supply terminals 4b. the

When an external electronic component is mounted in the mounting recess 4a, the charging terminal of the electronic component comes into contact with the power supply terminal 4b to supply DC power for charging. In this way, a power supply unit is constituted. The mounting recess (charging portion) may be provided not only on the front of the arm 5 but also on the side of the leg 4 or on the upper surface of the arm 5 at various positions that can be manipulated by the user. the

] 4) As the generator 15, instead of a PM type stepping motor, various driving motors such as a brushless motor and a DC motor can also be used.

5) The generator 15 can also be installed on the lower shaft driving the full-rotation needle cylinder or the half-rotation needle cylinder arranged in the base 3 in an externally embedded state, or installed on the bobbin thread winding device 13 ( Refer to Figure 1) on the bobbin drive shaft. In addition, instead of being built into the sewing machine 1, a rotating shaft that drives the sewing machine main shaft 8 to rotate through a belt or a gear may be provided outside the sewing machine 1, and may be attached to the rotating shaft. the

6) A rechargeable battery can be used instead of the disposable battery 44 . the

7) In order to prevent zero-setting processing due to erroneous operation of the reset switch 45, the zero-setting processing may be performed when the reset switch 45 is manipulated multiple times. the

8) The present invention is not limited to the above-mentioned embodiments, those skilled in the art can make various changes to the above-mentioned embodiments without departing from the scope of the present invention, and the present invention also includes these changes. the

9) It goes without saying that the present invention is applicable to all sewing machines provided with a sewing mechanism and a rotary shaft driven in rotation by a sewing machine motor or a drive shaft in reciprocating motion. the

Claims (4)

1. A sewing machine having a rotating shaft driven by a sewing machine motor, characterized in that it is provided with: a generator that is composed of a PM-type stepping motor mounted externally on the rotary shaft and generates electricity through the rotation of the rotary shaft, a power supply voltage control circuit that converts the generated power of the generator into a prescribed voltage, and Electronics powered from the supply voltage control circuit, The electronic device includes a CPU assembled in the sewing machine body, the power supply voltage control circuit has a stabilized voltage generating circuit for generating a power supply voltage of a prescribed voltage to be supplied to the CPU, The sewing machine is provided with a judging unit that judges the operation of the sewing machine by the rotational speed of the rotary shaft corresponding to the voltage level of the electric power generated by the generator, The CPU includes a cumulative operating time calculation unit that receives the output of the determination unit and accumulates operating times corrected by a correction coefficient corresponding to the rotational speed to calculate the cumulative operating time. 2. The sewing machine according to claim 1, characterized in that there is provided a prompting unit which is controlled by the CPU to prompt when the accumulated operating time reaches a predetermined value. 3. The sewing machine according to claim 1, characterized in that: said CPU includes a storage unit for storing the calculated accumulated running time, The sewing machine is provided with a reset switch for clearing the accumulated operation time stored in the storage unit. 4. The sewing machine according to claim 3, further comprising a battery for supplying power to the CPU when the reset switch is operated in a state where no power is generated by the generator.

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