JPS61172588A - Bobbin thread automatic feeder of sewing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Purpose of invention] [Industrial application field] [Conventional technology] In sewing machines, the bobbin thread is wound around a small bobbin.

When using a sewing machine, a bobbin is attached to a bobbin case, and the bobbin case is attached to an inner hook. Since the amount of thread wound around one bobbin is small, when operating continuously like an industrial sewing machine, the lower thread is consumed quickly and the lower thread needs to be replaced frequently. This type of bobbin thread replacement work is extremely troublesome and time consuming.

Therefore, in the technique disclosed in Japanese Patent Publication No. 42-15145, for example, the inner hook and the outer hook are formed into cylindrical shapes, and the bobbin case is inserted from one end of the hook and discharged from the other end. Moreover, the structure is such that a large number of bobbin cases are stored and pushed out one by one and inserted into the hook.

Therefore, the bobbin case can be replaced with a simple lever operation.

[Problems that JII Ming attempts to solve] However,
In the conventional technology, a person has to judge the presence or absence of the bobbin thread and replace it, but in order to accurately position it in the inner hook using a mechanism with a simple structure, the bobbin case to be replenished must be placed on the hook shaft. It is preferable to have a configuration in which a plurality of bobbin cases are held in a wavy manner in a cylindrical object arranged on an extension line, and the bobbin cases are pushed out from the rear side of the tube, and the bobbin cases are pushed out one by one from the front side of the tube. In that case, Since the installation space is restricted by each mechanism of the sewing machine body, it is not possible to store many bobbin cases in the cylindrical object at once, and continuous operation for long periods of time is not possible.

The present invention can store multiple bobbin cases at once.

The purpose is to enable unattended operation of sewing machines for long periods of time.

[Structure of the Invention] [Means for Solving the Problems] In order to achieve the above object, in the present invention, the inner hook and the outer hook are formed in a cylindrical shape so that the bobbin case can be penetrated in the axial direction of the tube. In addition, a conveying device for supplying bobbin cases to the hook and a bobbin case holding means for holding a large number of bobbin cases and supplying the bobbin cases one by one to the conveying device are provided.

and a second drive means for moving the pressing member in a direction perpendicular to the axis of the pot and positioning it at a predetermined position, and an electronic control means for controlling these.

[Function] For example, when the bobbin case needs to be replaced due to a low amount of bobbin thread remaining, one bobbin case is supplied from the bobbin case holding means to the gripping member, and the one gripping member is positioned at a predetermined position facing the shuttle mechanism. When the pressing member pushes out the bobbin case held by the gripping member, it pushes out the old bobbin case attached to the inner pot from one end of the inner pot, and a new bobbin case is inserted from the other end of the inner pot. Ru. in this case.

Since the bobbin case holding means can be arranged at a position offset from the rotation axis of the hook mechanism, there is less restriction on the arrangement space, and therefore a large number of bobbin cases can be stored in the bobbin case holding means.

By the way, in order to ensure reliable operation of this type of device, it is necessary to arrange a large number of sensors in each part and accurately position each part. However, it is preferable that the number of sensors be small. Therefore, in a preferred embodiment of the present invention, a detection means is provided to detect whether or not the pressing member is in a predetermined position, and the output is determined as to whether or not the gripping member is gripped. and.

A stepping motor is used as the first driving means to determine the reference position of the pressing member, and the position of the pressing member is determined by the number of driving steps. This reduces the number of sensors.

Embodiment] The present invention will be described in detail below with reference to the drawings. ' Figure 1, Figure 2, Figure 3, Figure 4, Figure 5, Figure 6a,
6b, 7, 8, 9 and 10,
Fig. 1 is a vertical cross-sectional view seen from the front, and Fig. 2 is a sewing machine bed 1 showing the mechanical part of an automatic bobbin thread supply device embodying the present invention.
Figure 3 is a vertical cross-sectional view as seen from the left side, Figure 4 is a scaled-down plan view, Figure 5 is a partial enlarged view of Figure 3, Figure 6a is a bobbin case. 15, FIG. 6b is a right side view of the bobbin case 15, FIG. 7 is a vertical sectional view showing the bobbin case magazine 291 with the bobbin case 15 attached, and FIG. 8 is a partially enlarged view of FIG. 9 is a side view taken along line IX--IX in FIG. 1, and figure 71gto is a cross-sectional view taken along line XX in FIG. 1.

This will be explained with reference to each drawing. As shown in FIGS. 2 and 3, a lower shaft sewing mechanism 100 is provided inside the sewing machine bed 1. A shuttle mechanism is provided below the needle 18. 2 is the inner pot, and 3 is the outer pot. The inner pot 2 and the outer pot 3 are each formed into a cylindrical shape, and the inside of the inner pot 2,
That is, one bobbin case 15 used for sewing is loaded into the through hole.

In this example, three elastic protrusions 16 are formed on the outer circumferential surface of the bobbin case 15, and these protrusions engage with annular grooves 2a formed on the inner circumferential wall of the inner hook 2. The bobbin case 15 is positioned in the axial direction of the inner hook 2. Furthermore, the two protrusions 2b provided on a part of the inner peripheral wall of the inner hook 2 engage with the recess 15a of the bobbin case 15, so that the bobbin case 15 is prevented from moving in the circumferential direction with respect to the inner hook 2. (see Figure 5).

The inner hook 2 is supported in a through hole of the outer hook 3 so as to be able to rotate once. The outer hook 3 is fixed to a cylindrical hook shaft 6 with a screw 5, and the hook shaft 6 is held in place by two needle bearings 9 located on its outer periphery. The bobbin case 15 can pass through.

A gear 6a is formed on a part of the outer periphery of the hook shaft 6.

A lower shaft gear 11 fixed to the lower shaft 10 meshes with this gear 6a. Therefore, when the lower shaft 10 is driven, its driving force is transmitted to the hook shaft 6, and the outer hook 3 rotates. Inner pot 2
is prohibited from rotating by the hook stopper 4 that engages with it, so it does not move even if the outer hook 3 is rotated.

In FIG. 2, the left side of the hook mechanism is provided with a solenoid SL3 for detecting the remaining amount of bobbin thread and a proximity sensor S5 for detecting the position of its rear flange. Although not shown, a conventionally known thread cutting mechanism is provided between the solenoid SL3 and the shuttle mechanism. 17 is a needle bar that supports the needle 18; 19 is a presser foot; 20 is a needle plate;
1 is a lint cover.

As shown by the imaginary line on the right side of the hook shaft 6 in FIG.
A transport mechanism, which will be described later, is positioned. This transport mechanism
3. Loading the bobbin case 15 into the inner hook 2 The bobbin case 15 will be described with reference to FIGS. 6a and 6b. Inside the bobbin case 15, there is a space for mounting the bobbin 13, and a guide shaft 1 formed in the center of the space.
Equipped with 5b. A bobbin stopper knob 14 for preventing the bobbin 13 from falling off is provided on the head of the guide shaft 15b. The bobbin stopper knob 14 is supported by a pin 22 on the head of the guide shaft 15b, and is rotatable in the direction of arrow AR5.

The guide shaft 15b has a cylindrical shape, and a push rod 24 and a compression coil spring 23 arranged around the outer periphery are installed inside the guide shaft 15b.
It has. The push rod 24 is a coil spring 23
The head presses the cam surface 14a of the bobbin stopper knob 14 due to the force.

The bobbin locking knob 14 positions itself in either the solid line position or the phantom line position shown in FIG. 6b, depending on the shape of its cam surface.

Reference numeral 25 denotes an idling prevention spring for preventing the bobbin 13 from idling during sewing, and is held between the head of the pushpiece 24 and the coil spring 23. Chapter 6a
The plate-shaped spring 26 shown in the figure is fixed to the bobbin case 15 with a screw 27, and is attached to the bobbin 13 of the thread 12.
The part pulled out from the thread 12 is held between the bobbin case 15 and tension is applied to the thread 12. The amount of tension can be adjusted by adjusting screw 28.

The bobbin 13 is composed of two cylindrical members 13A and 13B each provided with a flange, and the cylindrical portion 138a of the member 13B is fitted onto the outside of the cylindrical portion of the member 13A. The movement of the member 13B is restricted by the head of the cylindrical portion of the member 13A and a protrusion 13Aa formed on the cylindrical portion, but it is slightly slidable in the axial direction of the cylinder.

Therefore, the flange 13C of the bobbin 13 can be slightly expanded and contracted in the axial direction.

The thread 12 is wound with the flange 13C of the bobbin 13 stretched. When the thread 12 is wound, the cylindrical part 13Ba
A part of the thread is caught between the cylindrical part 138a and the protrusion 13Aa, and the thread prevents the movement of the cylindrical part 138a, so that the bobbin 13 normally maintains its stretched state. However, when the yarn wound around the bobbin 13 is consumed and the remaining amount of yarn decreases, the cylindrical portion 1
38a can now be moved. In this example, at a predetermined time, the solenoid SL3 shown in FIG.
In other words, the remaining amount of yarn is detected.

Next, the bobbin case feeding mechanism 210 provided below the sewing machine bed 1 will be explained. In this example, a large number of bobbin cases 15 to be attached to the inner pot 2 are loaded into three bobbin case magazines 291, 292, and 293, respectively, and stored so as to be automatically fed out one after another. As shown in FIGS. 4 and 7, each bobbin case magazine has a generally cylindrical shape, and has a cylindrical portion 29 that has a space inside for loading a large number of bobbin cases 15.
a, a base 29b that supports the bobbin case magazine; a long groove 29C formed throughout the axial direction to guide the protrusion 16 of the bobbin case; and a long groove 29C formed throughout the axial direction in the head of the cylindrical part. It has an opening 29d.

Plate-shaped magazine attachment fittings 30 and 31 made of a magnetic material are fixed to the base portion 29b of each bobbin case magazine by press-fitting and caulking. Each bobbin case magazine is arranged at a predetermined position on the magazine base 42 (see FIG. 4). Permanent magnets 44 are fixed to the magazine base 42 at positions facing the magazine mounting fittings 30, 31 of each bobbin case magazine. Therefore, each bobbin case magazine 291.29□ and 29
3 is held in place on the magazine base 42 by the attractive force of the magnet.

Magazine mounting bracket 3 fixed to each bobbin case magazine
0 indicates that one end thereof is bent as the engaging portion 30a. The magazine base 42 has respective engaging portions 30a.
A pushpiece 46 is placed at a position facing the. The pushbutton 46 is movably supported by a bush 45, and receives a force from a compression coil spring 47 to push the magazine mounting bracket 30 toward the left side in FIG. 8. A cylindrical slide head 65 is arranged at a position facing each push rod 46. The slide head 65 is connected to the cylinder shaft 63a of the air cylinder 63.
It sticks to the tip of the. 66 is a lock nut. When the air cylinder 63 is driven to push out the slide head 65, the slide head 65 pushes the engaging portion 30a against the force of the spring 47.

Each bobbin case magazine is engaged on the magazine base 42 by magnetic force, so when a force is applied, it slides on the magazine base 42 and moves to a position where the engaging part 30a abuts the end of the magazine base 42. , that is, the first
A solid line appears in the figure and FIG. When the slide head 65 returns to its original position, the force of the spring 47 causes the bobbin case magazine that has moved forward to return to its original retracted position.

The magazine base 42 is supported movably in the axial direction by a guide rod 41 oriented in a direction perpendicular to the axial direction of the bobbin case magazine.
It was screwed into the magazine base shaft nut 50 fixed to the magazine base 2. It is moved by rotating the threaded rod 39 parallel to the guide rod 41.

One end of the screw thread 39 is connected to the supply device base 3 via the bearing 38.
4, and the other end is connected via a joint 36 to a drive shaft of a stepping motor M2. , 37 are set screws.

A thin plate is attached to the end of the magazine base 42 (the left end in FIG. 4), and each bobbin case magazine 2
Magazine base positioning holes 491, 492, and 493 are opened at positions that coincide with the center portions of the shafts of 91, 292, and 293, respectively. On the supply device base 34,
Two transmissive optical sensors S4 and S6 are fixed. One end of the optical sensor is placed at a detection position.

In this example, when the optical sensor S4 detects the respective magazine base positioning holes 491, 49□ and 493, the bobbin case magazines 291, 292 and 293, respectively.
The centers of the cylindrical portions of the bobbin case magazines 291, 292, and 293 are aligned with the pressing portions 51a of the bobbin case feeding body 51, which will be described later, and the engaging portions 30a of the bobbin case magazines 291, 292, and 293 are aligned with the slide heads 65, respectively.

In the illustrated state, the optical sensor S4 detects the magazine base positioning hole 491, and the center of the cylindrical part of the bobbin case magazine 291 is aligned with the pressing part 51a of the bobbin case feeding body, so the bobbin case magazine 291 is selected. ing.

The bobbin case feeding body 51 is supported by a screw stud 58 and a guide rod 59 arranged in the axial direction of each bobbin case magazine, and when the screw rod 58 rotates,
move in the direction of its axis. One end of the threaded rod 58 is rotatably supported by the bracket 56 via the caulking metal 57, and the other end is connected to the stepping motor M via the joint 54.
1 drive shaft. A part of the bobbin case feeding body 51 is arranged as the pressing portion 51a at a position that coincides with the central axis of the bobbin case magazine being selected, as described above.

Therefore, by driving the stepping motor M1, the bobbin case payout body 51 moves, and when it moves to the right side in FIG. 1, the rearmost bobbin case in the selected bobbin case magazine is pushed in that direction. The bobbin case is paid out in the axial direction. In this example, the position shown by the imaginary line in FIGS. 1 and 8 is the home position of the bobbin case feeding body 51, and the proximity sensor S2 for detecting the bobbin case feeding body 51 is arranged at that position. It is.

A distance sensor S3 for detecting the distance between the pressing part 51a of the bobbin case feeding body and the rearmost bobbin case in the bobbin case magazine is mounted with the sensing surface facing the bobbin case side. It is.

Next, the bobbin case transport mechanism 2 transports the bobbin case in the bobbin case feeding mechanism 210 and loads it into the inner hook 2.
20 will be explained. A grip tube 69 for gripping one bobbin case inside is fixed to one end of the transport box 68. A through hole is provided in a portion of the transport box 68 that coincides with the central axis of the grip tube 69, and the extrusion rod 7 is inserted into the through hole.
0 is provided. A grip cylinder 69 is attached to the head of the extrusion piece 70.
The washer 72 and the detection plate 75 are circular and slightly smaller in diameter than the inner diameter of the washer 72 and the detection plate 75 are in the shape of a "<", and are engaged with the guide pin 76 through a hole formed in the center of the washer 72 and the detection plate 75, which is a compression coil attached to the guide pin 76. One arm of the detection plate 75, which receives a force directed toward the left side in FIG. A proximity sensor S1 is arranged at a position facing the other arm of the detection plate 75 (see FIG. 4).The proximity sensor S1 is fixed to the transport box 68.

In this embodiment, the proximity sensor Sl detects whether the bobbin case 15 is gripped by the grip cylinder 69 and the push rod 70.
detects whether or not it is at a predetermined reference position. That is, when the pushing rod 70 is moved to the right in FIG. 1, the washer 72 pushes the detection plate 75 to the right, and the proximity sensor S1
The detection status of changes. When the push-out bar 70 is positioned at this reference position, the proximity sensor S1 is always in the detection state.

Return the push rod 70 a little from that position and close the proximity sensor S1.
The state of the proximity sensor S1 changes, and it is detected that the first gripping cylinder 69 grips the bobbin case.

An air pipe 78 is formed slightly above the proximity sensor S1. One end of the air pipe 78 is connected to a high-pressure air source (not shown), and a nozzle 79 is formed at the other end. The nozzle 79 is arranged with its opening facing the inner space of the grip cylinder 69 and slightly inclined with respect to the axial direction.

The pushing rod 70 is formed with teeth, and a gear 73 meshes with the teeth. The gear 73 is a stepping motor M3.
is connected to the drive shaft of the The transport box 68 has a cylinder shaft 80a of an air cylinder 80 provided below,
It is supported by a guide rod 82 so as to be movable up and down relative to the supply device base 34 . 83 is a bearing of the guide rod 82.

FIG. 11 schematically shows the electric circuit of the sewing machine and the automatic bobbin thread supply device.The sewing machine main body 300 has the same construction as a conventionally known industrial sewing machine. The operation of the device is controlled by a microcomputer CPU. In this example, the microcomputer CPU includes a microprocessor MPU, a read-only memory ROM, a read/write memory RAM, an address decoder, a timing controller, an I10 port, and the like.

Proximity sensor Sl, S2. S5 and transmission optical sensor S
4. S6 has its output terminals directly connected to each other. The other input terminal of the analog comparator CMP.

A predetermined comparison voltage Vref is applied.

The switch SW1 connected to the I10 port is a mode switch for instructing the operation mode.

That is, in this example, three bobbin case magazines 29
Since 1, 29□ and 293 can be loaded at once and one of them can be selected, two operation modes can be selected depending on whether threads of the same color are attached to them or threads of different colors are attached to each. It looks like this.

Specifically, if the switch SWl is off, it is determined to be the first operation mode in which no thread color is specified, and when each bobbin case magazine becomes empty, the next bobbin case magazine is selected, and all bobbin case magazines are The bobbin cases are automatically replenished one after another until the bobbin cases run out. If switch SW2 is on, the second operation mode with thread color specification is determined, the bobbin case magazine is automatically selected according to the thread color information included in the sewing information, and the thread color of the bobbin thread is automatically changed. .

In the stepping motor M1, each output terminal of the driver Dv1 is connected to one end of each phase, and the other end of each phase is connected in common and connected to the output terminal of the driver DV5. A predetermined DC voltage VD is applied to the driver DV5. Similarly, drivers DV2 and DV6 are connected to stepping motor M2, and stepping motor M2 is connected to drivers DV2 and DV6.
3 is connected to drivers DV3 and DV7.

Each driver DVI, DV2 and DV3 is responsive to the signal level applied to its respective control input terminal.

On/off control is applied to the DC voltage VD applied to the output terminal.

The input terminals of the drivers DVI, DV2 and DV3 are connected to each other and commonly connected to the output terminal of the motor controller MCU. The motor controller MCU is
an excitation signal generator, in this example in response to a drive direction control signal cw/ccv and a clock pulse CLK applied to its input terminals;

Generates a 4-phase pulse signal. Drive direction control signal is CW
If it is at level, a pulse signal for forward rotation is output, and if it is at CCW level, a pulse signal for reverse rotation is output. The period of the pulse signal, that is, the driving speed of each stepping motor is determined by the period of the clock pulse CLK.

The output terminal of the multiplexer MPX is connected to the clock pulse input terminal of the motor controller MCU. The three signal input terminals of the multiplexer MPX are one connected to the output terminal of the oscillator O8C and the other input terminal connected to the I10 port of the computer of the oscillator O8C. Therefore, by controlling the state of this control terminal, the microcomputer CPU can control the driving speed of each stepping motor.

Each driver DV5. The control terminals of DV6 and DV7 are
Each is connected to the I10 port of the microcomputer CPU.

SLI, St2. St3 and St4 are solenoids. Solenoid SLI is a control solenoid for a solenoid valve that controls the air cylinder 80, solenoid SL2 is a control solenoid for a solenoid valve that controls the air cylinder 63, and St4 is a solenoid that controls air from a high-pressure air source connected to the air piping 78. This is a control solenoid for a solenoid valve that controls blowing on/off.

Each solenoid SLI, SL2. SL3 and St4 are
It is connected to each output terminal of driver DV4. Each input terminal of the driver DV4 is connected to the I10 port of the microcomputer CPU.

FIG. 12a shows the main routine, and the others show each subroutine. The operation of the CPU will be explained with reference to each drawing.

When the power is turned on, initial settings are performed first. In this initial setting, first set the output port level of the microcomputer CPU itself, clear the memory, set the mode, etc., and then set each mechanical part.In the initial state, air blowing is prohibited and the sewing machine stops. set to state,
The bobbin case magazine is set to the retracted position (return the plunger of the air cylinder 63), the magazine base 42 is set to the home position, and the push rod 70 is set to the home position (the position where 70 is slightly advanced after St is no longer turned on). ), the transport box 68 is set at the lower limit position (the position where the grip cylinder 69 matches the magazine), and the bobbin case payout body 51 is set at the home position (the position where S2 is turned on).

Next, the state of the mode switch SW1 is determined.

If it is on, set flag F1 to "1", if off, set Fl
Set “0” to “0”.

Set the motor M2 to normal rotation drive at ＼, and set the optical sensor S
4 is turned on for the first time. Since the magazine base 42 starts from the home position, the bobbin case magazine 29
1 is positioned to match the pressing portion 51a of the bobbin case feeding body. That is, the bobbin case magazine 291 is selected by this. At this time, 1 is set in register R1 in order to ascertain the type of magazine being selected.

When the above processing is completed, wait until there is an instruction to start operation, and when there is an instruction, determine the state of flag F1, and if it is It I It (thread color specified), execute "magazine exchange processing". Then, the process advances to the "bobbin thread replenishment process", and if the flag F1 is "O" (no thread color specified), the process immediately advances to the "r bobbin thread replenishment process". Briefly speaking, this "magazine exchange process"
Then, the bobbin case magazine to be positioned at the bobbin case payout position is selected and positioned according to the designated thread color.

In the "bobbin thread replenishment process", one bobbin case is paid out from the selected bobbin case magazine,
The work of loading it into the inner pot 2 via the transport mechanism 220 is performed. In other words, the presence or absence of an operation signal is checked in the initial state, and if there is an instruction, the sewing machine is operated accordingly. The sewing machine continues to operate until a predetermined sewing operation is completed. When the predetermined operation is completed, the sewing machine is stopped, a thread cutting operation (cutting the bobbin thread pulled out from the bobbin case loaded in the inner hook 2) is performed, and then a lower thread remaining amount detection operation is performed.

The bobbin thread remaining amount detection operation is performed by energizing solenoid SL3 and moving its plunger to bobbin 1 inside the bobbin case in the inner hook.
This is done by applying it to the flange of 3. As described above, the bobbin 13 maintains a stretched state in the axial direction depending on the remaining amount of yarn wound on it. The bobbin is allowed to shrink in the axial direction. Therefore, when the remaining amount of yarn is small, when the plunger of the solenoid SL3 hits the flange of the bobbin 13, the bobbin 13 contracts in the axial direction. In other words, the solenoid SL
The stroke of the plunger when energizing 3 changes. Proximity sensor S5 does not approach S5, so 85 remains off.

When the remaining amount of yarn decreases, the flange approaches 85, and 85 turns on at that time. Therefore, the remaining amount of yarn can be determined by monitoring the state of the proximity sensor S5 when the solenoid SL3 is energized.

If the thread remaining amount is low, a "bobbin thread replenishment process" is executed.

In addition, even if the remaining amount of thread is sufficient, the state of flag F1 is 7.
1171, that is, in a mode with thread color specification, it is checked whether there is a thread replacement instruction from the sewing program, and if there is such an instruction, the "magazine replacement process" is performed, and then the "bobbin thread replenishment process" is performed. Execute. Then, the process returns to the operation signal check process and the above operation is repeated.

The "magazine exchange process" will be explained with reference to FIG. 12b. In this process, first, the state of the flag Fl is checked, and processing is performed according to the result.

First, a case where the flag F1 is 711 #, that is, a case where thread color is specified will be explained. Note that if the thread color is specified, each bobbin case magazine 291, 292 and 29.
and store the values in register R according to the position where they are placed.
Load into 2. Compare the contents of registers R1 and R2,
If it matches, do nothing and return to the main routine. , R1<R2, the motor M2 is set to forward rotation drive; otherwise, the motor M2 is set to reverse rotation drive (signal CW/CCV is set).

Before starting the drive, the optical sensor S4 detects either of the magazine base positioning holes 4L1, 492 and 493 and is in the on state, but when the drive starts, the optical sensor S4 becomes the off state. Therefore, the next time the optical sensor S4 is turned on, the bobbin case magazine located next to the previously selected bobbin case magazine has reached the selected position. When optical sensor S4 turns on, the number of times it turns on is stored in register N.
is set (counted) and the contents of N are compared with the difference between registers R1 and R2. If they do not match, the motor M
2, and when they match, motor M2 is stopped, the contents of register R2 are set in register R1, and the process returns to the main routine.

The case where the flag F1 is "0", that is, the case where there is no thread color specification, will be explained. Return to setting motor M2 to normal rotation drive.

Referring to FIG. 12c, the lower thread replenishment process J will be explained.

Note that the following description will be made assuming that the bobbin case magazine 291 is selected. First, the solenoid SL2 is turned on, and the cylinder shaft 63a'r of the air cylinder 63 is pushed out. As a result, the slide head 65 coupled to the cylinder shaft 63a.

Engagement portion 3 of the magazine attachment fitting moves to the right in FIG. 1 and is fixed to the selected bobbin case magazine 291.
Press 0a. Therefore, the bobbin case magazine slides on the magazine base 42 and is positioned at a transport position close to the bobbin case transport device 220.

Next, the stepping motor M1 is set to normal rotation drive. When the motor M1 rotates forward, the screw 58 connected to its drive shaft rotates, and the bobbin case drawing body 51 screwed therewith moves toward the right in FIG. 1. After setting the motor M1 to normal rotation drive, the microcomputer CPU outputs a distance signal, that is, a distance sensor S3.
The direct output pulses of the oscillator O8C connected to the motor controller MCU are applied as clock pulses to the motor controller MCU.

Note that, at the same time as starting driving the motor M1, counting of the number of clock pulses applied to the motor controller MCU is started. In other words, by counting the number of clock pulses, the step value, that is, the distance traveled by the bobbin case feeding body 51 after the start of driving can be determined.

While the distance sensor S3 detects that the distance is not a predetermined short distance, the number of driving steps is checked.

N1 is the rear end of the bobbin case (the first
This value corresponds to a drive step at which it can be determined that the bobbin case payout body 51 has reached a position a distance corresponding to the short distance from the position (left end in the figure) by a distance corresponding to the short distance.

Normally, since the bobbin case magazine is not empty, the distance sensor S3 detects a short distance before the number of drive steps reaches N1. Sl detects the short distance and applies the pulse as a clock pulse to the motor controller MCU.

Next, the output state of the proximity sensor S1 is checked. In this case, the proximity sensor S1 is initially off, but the bobbin case located at the rightmost end in FIG. When the detection plate 75 is pressed through the washer 72, the proximity sensor S1 detects the detection plate 75 and turns on.

When the proximity sensor S1 is turned on, it is determined that the grip tube 69 has completely gripped the bobbin case 15, and the stepping motor M1 is stopped. Next, the speed signal is set to high speed again, and the stepping motor M1 is set to reverse drive. Therefore, the bobbin case payout body 51 is driven back toward the home position. Also, the solenoid SL2 is turned off and the plunger 63a of the air cylinder 63 is returned. Therefore, the engaging portion 30a of the magazine attachment fitting fixed to the bobbin case magazine 291 is attached to the push rod 46 at the mechanism 220.
move away from

The bobbin case magazine 291 is the bobbin case transport mechanism 2
20, turn on the solenoid SLI of the solenoid valve that controls the air cylinder 80, and turn on the solenoid SLI that controls the air cylinder 80a.
push upwards. As a result, the transport box 682
The grip cylinder 69 and the like are lifted upward. In this example, the grip cylinder 69 is positioned so as to exactly match the hook shaft 6 at its upper limit position. After this, when the proximity sensor S2 detects the bobbin case feeding body 51, that is, when the bobbin case feeding body 51 reaches the home position, the stepping motor M1
stop.

Next, the solenoid SL4, which is a solenoid valve that controls air blowing from the nozzle 79, is turned on to start blowing air from the nozzle 79.

As shown in FIG. 5, each bobbin case 15 is
One end of the thread is pulled out from the front, but the thread may get caught in the surrounding mechanism. However, in this embodiment, since the air is blown out from within the gripping cylinder, the air flows through the surface of the bobbin case 15 and is therefore not pulled out of the bobbin case and trapped. In addition, since the hook rotates at high speed in the hook mechanism, the generation of lint is unavoidable.
The airflow blown out from the nozzle 79 blows away lint and the like adhering to various parts of the hook mechanism toward the tip, so that the hook mechanism is automatically cleaned.

Subsequently, the stepping motor M3 is set to normal rotation drive, and the pushing rod 70 is driven toward the left side in FIGS. 1 and 2. At the same time, motor controller MC
Counting of the clock pulses applied to U is started, and the amount of drive of the extrusion bar 70 is ascertained. Check the number of drive steps and wait until it reaches a predetermined value N3. This predetermined value N
3 is a bobbin case 15 located at the tip of the extrusion bar 70;
Distance (number of steps) from the home position that the pushing rod 70 is driven until it is completely loaded into the inner pot 2
corresponds to

When the push-out rod 70 is driven, the bobbin case held in the gripping cylinder 69 is pushed out from the gripping cylinder 69 and moved to the second
As shown by the imaginary line in the figure, set the hook shaft to the fixed state,
Then set it to reverse drive.

Then, the state of the proximity sensor S1 is checked. The proximity sensor Sl is turned on when the grip tube 69 grips the bobbin case 15, but turns off again when the pusher rod 70 is driven and pushes the bobbin case out of the grip tube 69.

Then, when the push rod 70 enters the grip cylinder 69 and returns further, the washer 72 coupled thereto pushes the detection plate 75,
This turns on the proximity sensor S1 again.

When proximity sensor S1 turns on, stepping motor M3
Then, turn off solenoid SL4 and turn off nozzle 7.
Stop air blowing from 9. Next, solenoid SL
I is turned off, the cylinder shaft 80a of the air cylinder 80 is moved backward, and the transport box 68 is lowered to the lower limit position.

Finally, the stepping motor M3 is driven in normal rotation while monitoring the state of the distance sensor S1, and when Sl is turned off, the motor M3 is stopped. This enables the next bobbin case supply operation.

Case 1 of driving the bobbin case feeding body 51 for feeding out the bobbin case in the bobbin case magazine 291
Normally it works as above, but sometimes the bobbin case magazine is empty. In that case, after setting the speed signal to high speed, the number of drive steps of stepping motor M1 is N.
Exceeds 1.

When this is detected, the stepping motor M1 is immediately set to reverse drive, and the bobbin case payout body 51 is driven in the return direction to return it to the home position.

When the bobbin case feeding body 51 reaches the home position, the stepping motor M1 is stopped and the solenoid S
Set L2 off.

Here, the state of flag F1 is checked. If the flag F1 is . However, if the content of register R1 is 3, all bobbin case magazines are empty, so "magazine empty processing" is executed. If the flag F1 is 1'', that is, if the thread color is specified, the ``magazine empty process'' is executed regardless of the state of the register R1.

"Magazine empty processing" will be explained with reference to FIG. 12d.

First, set the stepping motor M2 to reverse drive,
Motor M2 is driven until optical sensor S6 is turned off.

Thereby, the magazine base 42 is positioned at a predetermined home position where it is easy to attach and detach the bobbin case magazine. It then displays that the magazine is empty and waits for the replenishment process to be completed.

When the replenishment work is completed, clear the magazine empty display, set the stepping motor M2 to normal rotation drive, position the magazine base 42 so that the bobbin case magazine 291 is selected, and set 1 to the register R1 to start the main Return to routine.

Figures 13a and 13b show modified examples of the bobbin case. In this bobbin case 90, in order to stop movement in the circumferential direction, each of the two "L" shaped metal fittings -
Sides 91a and 92a are arranged on the outer peripheral surface thereof. The other sides of these metal fittings 91 and 92 are each supported by the bobbin case 90 so as to be slidable in the IL radial direction, and the sliding range thereof is regulated by a protrusion (9lb>, etc.).

Further, one end of the metal fittings 91 and 92 is connected to a compression coil spring 93-south 93 whose center portion is fixed to the bobbin case 90.
It protrudes to the outer periphery of 0. However, when each of the metal fittings 91 and 92 receives a force directed toward the center of the bobbin case 90 from the outside, it retreats to a position inside the outer periphery of the bobbin case 90.

In addition, when using the bobbin case 90 of this modification, depending on the shape and position of the metal fittings 91 and 92, grooves (for example, 2
It is necessary to change the shape and position of 9C).

In the above embodiment, for example, the bobbin case payout body 51 of the bobbin case payout mechanism 210 is driven by a mechanism using a screw stud (58), but a structure in which the driving force is transmitted using, for example, a timing belt You can also do this.

In the above embodiment, the transport box 68 and the like are driven in the vertical direction using the air cylinder 80, but they may also be driven using an electric motor such as a stepping motor. Not limited to the direction, but also the horizontal direction (
(Horizontal direction) However, in the case of a general sewing machine, each mechanism M is the effect of the invention. 41. Since the bobbin case is automatically replaced, no human work is required, and the sewing machine can be operated unmanned. especially,
Since the bobbin case holding means can be placed at a position offset from the drive shaft of the hook mechanism, the number of bobbin cases that can be stored at one time in the holding means increases, and operation is not interrupted for a long time to replace the bobbin cases. The sewing machine can be operated continuously without any trouble.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view showing the automatic bobbin thread supply mechanism 200, and FIG.
The figure is an enlarged vertical cross-sectional view showing the lower shaft sewing mechanism 100, FIG. 3 is a vertical cross-sectional view seen from the left side of FIG. 1, FIG. 4 is a reduced plan view showing the bobbin thread automatic supply mechanism 200, and FIG. is a partially enlarged view of FIG. 3, FIG. 6a is a front view of the bobbin case 15, and FIG. 6b is a partial enlarged view of FIG.
The figure is a partially cutaway right side view of the bobbin case 15, FIG. 7 is a longitudinal sectional view of the bobbin case magazine loaded with the bobbin case, FIG. 8 is an enlarged longitudinal sectional view of the bobbin case feeding mechanism 210, and FIG. 9 is the bobbin case Case Transport Mechanism 220 FIG. 12a is a flowchart showing the general operation of the microcomputer CPU shown in FIG. 11, and FIGS. 12b, 12e, and 12d are flowcharts showing the operation of each subroutine of the CPU. Figures 13a and 13b are a front view and a partially cutaway right side view showing a modification of the bobbin case. 1: Sewing machine bed 2: Inner hook 2a: Inner hook groove 2b: Inner hook protrusion 3: Outer hook
4: Hook stopper 5: Screw 6: Hook shaft 6a: Gear 7, 8: Washer 9: Needle bearing lO: Lower shaft 11: Lower shaft gear 12: Lower thread
13: Bobbin 13A, 13B: Members constituting the bobbin 13Aa: Protrusion, 13Ba: Cylindrical portion 14: Bobbin stopper knob 14a: Cam surface 15: Bobbin case 16: Protrusion 21: Lint cover 22: Pin 23: Coil spring 24 : Push-piece 25: Idling prevention spring 26 Two-plate spring 27: Screw 28: Adjustment screw 29t r 292 t 293 : Bobbin case magazine 29a: Cylindrical part, 29b: Base, 29c: Long groove. 29d: Opening portion 30.31: Magazine mounting bracket 30a: Engagement portion 32: Stopper 33: Flat head screw
34: Sewing machine base 36: Joint 3
7: Set screw 38: Bearing 39: Screw 40: Set screw 41 Guide rod 42: Magazine base 42a: Detection plate 43: Magazine positioning groove 44: Permanent magnet 45: Push 46: Push 47: Coil spring 491, 49 □, 49a: Magazine base positioning hole 50: Magazine base shaft nut 51: Bobbin case feeding body 59 Ni guide rod 60: Nut 63: Air cylinder 63a Niji cylinder shaft 65 Ni slide head 66: Lock nut 68: Transport box
69: Gripping tube (gripping member) 77: Coil spring 78: Air piping 79: Nozzle 80: Air cylinder (second driving means) 80a Niji cylinder shaft 82 Ni guide rod 83: Bearing 84: Bobbin case receiver 85: Bobbin case collection box 100: Lower shaft sewing mechanism 200: Automatic bobbin thread supply mechanism 210: Bobbin case feeding mechanism (bobbin case holding means) 220: Bobbin case transport mechanism ARI to AR6: Arrow elbow, 2. M3 Varnish chipping motor (first drive means) SLI, SL2. SL3. SL4: Solenoid S
l, S2. S5: Proximity sensor S3: Distance sensor S4. S6: Transmissive optical sensor swi: Mode switch CPU: Microcomputer (electronic control means) CMP
:Analog comparator patent applicant Todoroki Datsuto, Director of the Agency of Industrial Science and Technology 5 Figure 6a Figure 6b Figure 7 and 0. ” Figure 9 East Figure 10 Figure East 12b <7 is 1 drop ε tarri> East + 2d Figure h413a Figure ql East Figure 13b

Claims (5)

[Claims] (1) A hook mechanism having a cylindrical inner hook and an outer hook; a gripping member that grips one bobbin case; a bobbin case holding means that holds a plurality of bobbin cases and sequentially supplies the bobbin cases to the gripping member; a pressing member that passes through the gripping member and moves in the direction of an axis parallel to the rotational axis of the hook mechanism; a first driving means for driving the pressing member; a second driving means that moves in an orthogonal direction and positions it at a position facing the hook mechanism and a position facing the bobbin case holding means; and controlling the driving means and the second driving means of item 1; When the predetermined support is obtained, the gripping member is positioned at a position facing the bobbin case holding means, the bobbin case is supplied to the gripping member, the gripping member is positioned at a position substantially coinciding with the rotation axis of the hook mechanism, and the gripping member is pressed. An automatic bobbin thread supply device for a sewing machine, comprising: an electronic control means for driving a member to attach a bobbin case held by a gripping member to a shuttle mechanism; (2) The automatic bobbin thread supplying device for a sewing machine according to claim 1, wherein the gripping member includes a gripping detection means for detecting whether or not the bobbin case is gripped. (3) The grip detection means detects whether the pressing member is in a predetermined position, and the electronic control means monitors the detection output of the grip detection means, positions the pressing member at a predetermined reference position, and When the gripping member grips the bobbin case in this state,
The automatic bobbin thread supply device for a sewing machine according to claim (2), wherein the gripping member is positioned in a position facing the hook mechanism, the pressing member is moved by a predetermined amount, and the bobbin case is attached to the hook mechanism. . (4) The automatic bobbin thread supplying device for a sewing machine according to claim (1), wherein the first driving means is a stepping motor. (5) Claims (1), (2), (3), or (4), wherein the second driving means includes an air cylinder and a solenoid valve that controls the air cylinder. Automatic bobbin thread feeding device for the sewing machine described.