JPS61172583A - 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] [Object of the Invention] [Industrial Application Fields] The present invention is applicable to industrial sewing machines, which operate virtually continuously for long periods of time and require frequent replacement of the bobbin thread. This invention relates to an automatic bobbin thread supply device used in sewing machines.

[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 on one bobbin is small, when operating continuously like in an industrial sewing machine, the bobbin thread is consumed quickly, and the bobbin case must be removed from one end of the hook. It is configured to be inserted from one end and ejected 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 to be Solved by the Invention] However, in the conventional technology, a person has to determine whether there is a bobbin thread and replace it, so in any case, an operator is required to monitor the sewing machine. When a large number of sewing machines are operated at the same time, it is difficult for the operator to monitor and replace the bobbin thread. Furthermore, when replacing the bobbin case mechanically by operating a lever or the like, processing of the end of the thread pulled out from the bobbin becomes a problem. That is, when setting a new bobbin case, it is necessary to pull out one end of the thread from a part of the bobbin case, but there is a risk that the thread end may get caught in the surrounding mechanism during movement, causing trouble. In addition, for industrial sewing machines that operate continuously at high speed, the present invention aims to automate thread replenishment, improve the reliability of bobbin case replacement operations, and prevent troubles caused by thread waste.

[Structure of the invention [Means for solving the problem] 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. At the same time, a holding means for holding at least one bobbin case, a pressing member that moves in the axial direction of the cylinder, a driving means for driving the pressing member, an electronic control means for controlling the driving means, and a bobbin case placed in the inner pot. A nozzle or the like is provided to blow out a gas such as air in the direction of attachment, and when the bobbin thread needs to be replaced, the bobbin case is automatically replaced by driving the pressing mechanism and blowing out the gas in a predetermined direction.

[Operation] For example, when a bobbin thread replacement instruction is issued by the sewing program, the electronic control means controls the drive means to move the suppression mechanism in the axial direction of the hook. This allows it to enter from the other end of the inner pot and be attached to the inner pot instead. Also, since air, etc. is blown out in the direction of movement of the bobbin case, the end of the thread pulled out from the bobbin case is directed in the direction of the air flow, that is, in front of the bobbin case, so that it is not caught in the surrounding mechanism. Never. In addition, the flow of air blows off lint and the like that have previously adhered to the hook, thereby cleaning the hook mechanism.

In order to reliably position the end of the thread pulled out from the bobbin case and to clean the hook mechanism, it is necessary to increase the pressure of the air blown out from the nozzle. However, in order to generate a large amount of high-pressure air, a large compressor must be installed. Therefore, in a preferred embodiment of the present invention, a solenoid valve is provided to control the air blowing from the nozzle, and except when replacing the bobbin case,
Prohibits air blowing from the nozzle to reduce high pressure air consumption.

[Embodiment] FIG. 10 shows a mechanical section of an automatic bobbin thread supply device embodying the present invention. Fig. 1 is a longitudinal sectional view seen from the front, Fig. 2 is an enlarged sectional view showing the inside of the sewing machine bed 1, Fig. 3 is a longitudinal sectional view seen from the left side, and Fig. 4 is a scaled-down plan view. , Figure 5 is a partially enlarged view of Figure 3, Figure 6a is bobbin case 1.
5 is a front view of the bobbin case 15, and FIG. 6b is a right side view of the bobbin case 15.
FIG. 7 is a longitudinal sectional view showing the bobbin case magazine 291 with the bobbin case 15 attached, FIG. 8 is a partially enlarged view of FIG. 1, and FIG. 9 is a side view taken from line IX-IX in FIG. FIG. 10 is a sectional view taken along the line X--X 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, by engaging one bobbin case 1a used for sewing in the through hole, the bobbin case 15
It is positioned in the axial direction of the inner pot 2. Further, two protrusions 2b provided on a part of the inner circumferential wall of the inner pot 2 are connected to the bobbin case 15.
By engaging with the recess 15a of the bobbin case 15
is positioned so as not to move in the circumferential direction with respect to the inner pot 2 (see FIG. 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 tubular hook shaft 6 with a screw 5, and the hook shaft 6 is the outer periphery of the hook shaft 6. The pot shaft 6 is
Its inner diameter matches the inner diameter of the inner hook 2, and the bobbin case 15 can pass through the through hole.

A gear 6a is formed on a part of the outer periphery of the hook shaft 6, and a lower shaft gear 11 fixed to a 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
Rotation is prohibited by the hook stopper 4 that engages with it, so even if the outer hook 3 is rotated, it does not move.

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
Load the bobbin case 15 into the inner hook 2.

The bobbin case 15 will be explained with reference to FIGS. 6a and 6b. Inside the bobbin case 15.

A space for mounting the bobbin 13 and a guide shaft 15b formed in the center thereof are provided. 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 indicated by an arrow AR5.
It is possible to rotate in the direction.

The cam surface 14a of the bottle locking knob 14 is pressed.

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

Reference numeral 25 designates an idling prevention spring for preventing the bobbin 13 from idling during sewing, and is held between the head of the push rod 24 and the coil spring 23. Chapter 6a
The plate-shaped spring 26 shown in the figure is fixed to the bobbin case 15 by a screw 27, and applies tension to the thread 12 by sandwiching the portion of the thread 12 pulled out from the bobbin 13 with the bobbin case 15. The amount of tension is determined by adjusting screw 2.
8.

The bobbin 13 is composed of two cylindrical members 13A and 13B each provided with a flange, and the cylindrical portion 13Ba 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 the protrusion 13Aa formed on the cylindrical portion, but the member 13B is wound in a cylindrical state. When the thread 12 is wound, a part of the thread is caught between the cylindrical part 13Ba and the protrusion 13Aa, and this thread prevents the movement of the cylindrical part 13Ba, so the bobbin 13 is normally in a stretched state. maintain. However, when the yarn wound around the bobbin 13 is consumed and the remaining amount of yarn decreases, the cylindrical portion 13Ba becomes movable. In this embodiment, at a predetermined time, the solenoid SL3 shown in FIG. Detects the remaining amount of thread.

Next, the bobbin case feeding mechanism 210 provided below the sewing machine bed l 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 shape with a space inside for loading a large number of bobbin cases 15. A long groove 29C9' formed over the entire length and an opening 29d formed over the entire axial direction in the head of the cylindrical part.
It is equipped with

At the base 29b of each bobbin case magazine.

Plate-shaped magazine attachment fittings 30 and 31 made of magnetic material are fixed 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 291t 292 and 293 is attached to the magazine base 4 by the attractive force of the magnet.
is held in place on 2.

Magazine mounting bracket 3 fixed to each bobbin case magazine
0 indicates that one end thereof is bent as the engaging portion 30a. In the magazine base 42.

A push rod 46 is arranged at a position facing each engaging portion 30a. The push rod 46 is movably supported by a bush 45 and is supported by a compression coil spring 47.
The magazine attachment fitting 30 is subjected to a force that presses it toward the left side in FIG. 8.

A cylindrical slide head 65 is arranged at a position facing each push rod 46 with each engaging portion 30a in between. In the slide head 65, the air cylinder 63 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
The bobbin case magazine is advanced to the position shown by the solid line 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 stud 39 parallel to the guide rod 41.

The threaded rod 39 has one end connected to the feeder base 3 via the bearing 38.
4, and the other end is connected via a joint 36 to the drive shaft of a stepping motor M2. 37 is a set screw.

A thin plate is attached to the end of the magazine base 42 (the left end in FIG. 4), and each bobbin case magazine is mounted on the thin plate.
Magazine base positioning holes 491, 492, and 493 are opened at positions that coincide with the center portions of the shafts of jlts 292 and 293, respectively. On the supply device base 34,
Two transmissive optical sensors S4 and S6 are fixed. The optical sensor S4 is located in the magazine base positioning hole 491.
．． 492 and 493, and the optical sensor S6 is arranged at a position to detect one end of the thin plate when the magazine base 42 is at the home position (retracted position).

In this example, when the optical sensor S4 detects the magazine base positioning holes 491, 492 and 493, the bobbin case magazines 291, 292 and 293, respectively.
The center of the cylindrical portion coincides with a pressing portion 51a of a bobbin case feeding body 51, which will be described later.

Bobbin case magazines 291, 292 and 2 respectively
The engaging portion 30a of 93 is aligned with the slide head 65 described above.

In the illustrated state, the optical sensor S4 is aligned with the pressing portion 51a of the magazine bay, so the bobbin case magazine 2
91 is selected.

The bobbin case feeding body 51 is supported by a threaded rod 58 and a guide rod 59 arranged in the axial direction of each bobbin case magazine, and when the threaded 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 suppressing part 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 feeding body 51 is moved.

When the bobbin case moves to the right in FIG. 1, the rearmost bobbin case in the selected bobbin case magazine is pushed in that direction, and the bobbin case is fed 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 payout body 5I, and a proximity sensor S2 for detecting the bobbin case payout body 51 is arranged at that position. It is.

Note that a distance sensor S3 for detecting the distance between the suppressing part 51a of the bobbin case feeding body and the rearmost bobbin case in the bobbin case magazine is mounted with the detection 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.
A washer 72 and a reciprocating body 71, which are circular and have a diameter slightly smaller than the inner diameter of the inner diameter, are fixedly attached.

God, one end is a little below the stick 70, and the transport box -6
8 is provided with a guide pin 76 fixed thereto.

The detection plate 75 has a "<" shape, and is engaged with the guide pin 76 through a hole formed in its center.
A compression coil spring 77 attached to the body receives a force directed to the left in FIG. One arm of the detection plate 75 is arranged in the inner space of one grip cylinder 69. 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 S1 detects whether or not the bobbin case 15 is gripped by the grip tube 69, and the push-out rod 70.
detects whether or not it is at a predetermined reference position. That is, when the push-out bar 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 rod 70 is positioned at this reference position, the proximity sensor Sl will always be in the detection state, so move the push rod 70 back a little from that position and move the home position holding cylinder 69 to the position where the proximity sensor S1 is in the non-detection state.
is detected to have gripped 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 shows an outline of the electric circuit of the sewing machine and the automatic bobbin thread supply device. The sewing machine main body 300 is composed of a RAM, an address decoder, a timing controller, an I/○ port, etc., similar to those of conventionally known industrial sewing machines.

Proximity sensor St, S2. S5 and transmission optical sensor S
4 and 36, their output terminals are directly connected to the I10 port, the output terminal of the distance sensor S3 is connected to one end of the analog comparator CMP, and the output terminal of CMP is connected to the I10 port.
Attached to the boat. The other input terminal of the analog comparator CMP.

A predetermined comparison voltage Vref is applied.

A switch SWI connected to the I10 boat is a mode switch for instructing the operating mode.

That is, in this example, three bobbin case magazines 29
Since 19292 and 293 can be loaded at once and one of them can be selected, two operating modes can be selected depending on whether they are loaded with threads of the same color or threads of different colors. ing.

Specifically, if the switch SWI is off, bobbin cases are automatically replenished one after another until there are no more bobbin cases in the thread color gin. If switch SW2 is on, the second operation mode with thread color specification is determined, the bobbing smagazine 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, one end of each phase is connected to each output terminal of the driver DVI, and the other end of each phase is commonly connected 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 of the drivers DVI, DV2, and DV3 sets the output terminal to an on level (ground) or an off level depending on the signal level applied to the control input terminal. Driver DV5. DV6 and DV7.

Application of the DC voltage VD to the output terminal is controlled to be on/off depending on the signal level applied to the control input terminal.

In this example, four-phase pulse signals are generated according to the drive direction control signal Cw/CCV and clock pulse CLK applied to the input terminal. If the drive direction control signal is at CW level, a pulse signal for forward rotation is output, and from 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.

One of the signal input terminals is connected to the output terminal of the oscillator O8C, the other is connected to the output terminal of the divider DVD whose input terminal is connected to the output terminal of the oscillator oSC, and the remaining one
One is grounded. The two control terminals of multiplexer MPX are connected to the I10 port of the microcomputer. 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 10 ports of microcomputer CPU.

SLI, SL2. SL3 and SL4 are solenoids. Solenoid SL1 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 SL4 is a solenoid that controls air from a high-pressure air source connected to air piping 78. This is a control solenoid for a solenoid valve that controls blowing on/off.

Each solenoid SLI, SL2. SL3 and SL4 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.

12a, 12b, 12c and 12d schematically show the operation of the microcomputer CPU. Note that 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, the output port level of the microcomputer CPU itself is initialized, the memory is cleared, the mode is set, etc., and then each mechanical section is set. In the initial state, air blowing is prohibited and the sewing machine is set to a stopped 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 Sl 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 II O17 to .

Next, set motor M2 to normal rotation drive, and 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.

Once the above processing is complete, wait until you receive an instruction to start operation. When there is an instruction, the state of flag F1 is determined, and if it is II I It (thread color specified), the "magazine exchange process" is executed, and then the process proceeds to the "bobbin thread replenishment process", and when the flag F1 is 11011 (thread color specified). (No color specified), immediately proceed to "bobbin thread replenishment process". Briefly, in the "magazine exchange process", a 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 one selected bobbin case magazine,
The work of loading it into the inner pot 2 via the transport mechanism 220 is performed. That is, in the initial state, it is determined that the bobbin case is not attached to the inner pot 2, and the bobbin case replenishment operation is performed without any special instruction.

Checks whether there is a running signal and operates the sewing machine according to the instructions. 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 detects the rear flange connected to the plunger of solenoid SL3, and if there is enough yarn remaining, the flange will not approach 85, so 85 will remain off, but if the remaining yarn amount is low, the flange will remain off. approaching 85,
At that time, 85 turns on. Therefore, by monitoring the state of the proximity sensor S5 when the solenoid SL3 is energized,
The amount of thread remaining can be determined.

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

Furthermore, even if the remaining amount of thread is sufficient, the state of flag F1 is I
t I 11, that is, the mode with thread color specification, checks whether there is a thread replacement instruction from the sewing program, and if there is such an instruction, performs "magazine replacement processing" and then performs "bobbin thread replenishment". Execute "Processing". 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, the state of the flag F1 is first checked, and processing is performed according to the result.

First, the case where the flag F1 is rt 1 It, that is, the case where the thread color is specified will be explained. In addition, if the thread color is specified, each bobbin case magazine 291+292 and 2
93 is equipped with a bobbin wound with thread of a predetermined color according to the position where they are placed.
Compare the contents of 6 registers R1 and R2 to be loaded into 2,
If it matches, do nothing and return to the main routine. If R1<R2, set motor M2 to normal rotation drive.

If not, set motor M2 to reverse drive (signal C
Set W/CCV).

Before starting the drive, the optical sensor S4 detects any one of the magazine base positioning holes 491, 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, set (count) the number of times it turns on in register N, and store the contents of N in registers R1 and R2.
Compare with the difference. If they do not match, continue driving the motor M2, and if they match, stop the motor M2,
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 IFO'1, that is, the case where there is no thread color specification, will be explained. The motor M2 is returned to normal rotation drive.

The "bobbin thread replenishment process" will be explained with reference to FIG. 12c.

Note that the following description will be made assuming that the bobbin case magazine 291 is selected. First, the solenoid SL2 is turned on to let out the cylinder shaft 63a of the air cylinder 63.

As a result, the slide head 65 coupled to the cylinder shaft 63a moves to the right in FIG. 1 and presses the engaging portion 30a of the magazine attachment fitting fixed to the selected bobbin case magazine 291. 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.
Monitor the state of the output signal of the analog comparator CMP connected to.

If the distance is greater than a predetermined value, the speed signal is set to high speed. That is, by controlling the multiplexer MPX, the oscillator O8C
The direct output pulses of the clock valve are applied 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
The bobbin drawer 51 has reached a position a distance corresponding to the short distance from the position (left end in the figure). This value corresponds to a drive step that can be determined to be .

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 a short distance and sets the speed signal to low speed. That is, by controlling the multiplexer MPX, a pulse signal having a relatively long period obtained at the output terminal of the branch divider DVD is applied as a clock pulse to the motor controller MCU.

Next, the output state of the proximity sensor Sl 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 29r is returned to the retracted position by the push rod 46, and the tip of the bobbin case magazine 291 (the right end in FIG. 1) is moved away from the bobbin case transport mechanism 220. Leave.

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 689
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 inside the gripping cylinder, the air flows through the circumferential surface of the bobbin case 15, so that the end of the thread pulled out from the bobbin case is caused to flow in the direction of the air flow. Since it does not touch the surrounding mechanism, it will not get caught in the mechanism part. In addition, since the hook rotates at high speed in the hook mechanism, the generation of lint is unavoidable, but the airflow blown out from the nozzle 79 blows away the lint, etc. attached to various parts of the hook mechanism toward the tip. , so the kettle mechanism is automatically cleaned.

Subsequently, the stepping motor M3 is set to normal rotation drive to drive the push rod 70 toward the left 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 push rod 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 first gripping cylinder 69, and the bobbin case is pushed out from the second gripping cylinder 69.
As shown by the imaginary line in the figure, it is pushed into the inside of the hook shaft 6, further advanced, and set at a predetermined position inside the inner hook 2. When the bobbin case is attached to the inner hook 2, the stepping motor M3 is set to a stopped state, and then set to reverse drive.

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

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.
6 to stop air blowing from 9, 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.

When driving the bobbin case payout body 51 to pay 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.

The bobbin case feeding body 51 checks the state of the flag F1 here. If the flag F1 is nO'', that is, no thread color is specified, the "magazine exchange process" is executed and another bobbin case magazine is selected. However, if the content of register R1 is 3, all bobbin case magazines are empty, so "magazine empty processing" is executed. Flag F1 is II
I11, that is, if thread color is specified, "magazine empty processing" is executed regardless of the state of 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 at the position K where the bobbin case magazine 291 is selected, and set 1 in the register R1. Return to main routine.

Figures 13a and 13b show modified examples of the bobbin case. In this bobbin case 90, in order to stop the movement in the circumferential direction, each of the two rLJ-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 radial direction, and the sliding range thereof is regulated by a protrusion (9lb) or the like. Further, one ends of the metal fittings 91 and 92 are coupled to both ends of a compression coil spring 93 whose central portion is fixed to the bobbin case 90.

Therefore, the metal fittings 91 and 92 are always subjected to a force directed toward the outside of the bobbin case 90 by the spring 93, so that normally each side 91a, 92a protrudes to the outer periphery of the bobbin case 90. 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 threaded rod (58), but a structure in which the driving force is transmitted using, for example, a timing belt may also be used. You can also do this.

In the above embodiment, the air blowing nozzle 7
9 was opened into the inner space of the grip cylinder 69.

For example, a nozzle may be opened at a position between the grip cylinder 69 and the hook shaft 6 toward the inner space of the hook shaft 6.

Further, in the embodiment, there is one nozzle, but a plurality of nozzles may be arranged, or, for example, the opening of the nozzle may be formed in an annular shape to match the shape of the bobbin case.

[Effects of the Invention] As described above, according to the present invention, the bobbin case is automatically replaced when a predetermined instruction is given.

This eliminates the need for human work and enables unmanned operation of the sewing machine. In addition, since air or other gas flows through the bobbin case passage when the bobbin case is attached, troubles such as thread ends getting caught in other mechanical parts can be prevented, and lint, cloth waste, etc. are automatically removed, resulting in malfunctions. can be prevented from occurring.

[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 sectional view showing the lower shaft sewing mechanism 100, and FIG. 3 is a vertical sectional view seen from the left side of FIG. FIG. 4 is a reduced plan view showing the automatic bobbin thread supply mechanism 200, FIG. 5 is a partially enlarged view of FIG. 3, and FIG. 6a is a bobbin case 1.
5 is a front view, FIG. 6b is a partially cutaway right side view of the bobbin case 15, FIG. 7 is a vertical sectional view of the bobbin case magazine loaded with the bobbin case, and FIG. 8 is an enlarged vertical sectional view of the bobbin case feeding mechanism 210. Figure 9 is a left side view of the bobbin case transport mechanism 220 (line IX-II in Figure 1),
The figure is a sectional view taken along the line X--X in FIG. 1. FIG. 11 is a block diagram showing the electrical circuit of the sewing machine. Figure 12a shows the microcomputer CP shown in Figure 11.
Flowchart showing the general operation of U, Fig. 12b, 1st
2c 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 (supporting member) 10: Lower shaft 11: Lower shaft gear 12: Lower thread
13: Bobbin 13A, 13B: Members constituting the bobbin 13Aa: Protrusion, 13Ba: Cylindrical portion 14: Bobbin stop knob 14a: Cam surface 15: Bobbin case 16: Protrusion 17: Needle bar 18: Needle 19: Presser foot 20: Throat plate 21: Lint cover 22: Pin 23: Coil spring 24: Push rod 25: Idling prevention spring 26: Plate spring 27: Screw 28: Adjusting screw 291 v 292 e 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: Threaded rod 40: Set screw 41 Guide rod 42: Magazine base 42a: Detection plate 43: Magazine positioning groove 44: Permanent magnet 45: Push 46: Push rod 47: Coil spring 491 + 492 t 49a: Magazine base positioning hole 50: Magazine base shaft nut 51: Bobbin case feeding body 52 nib bracket 54 Joint 55: Set screw 56: Bracket 57: Caulking metal 58: Screw stud 59 guide rod 60: Nut 63: Air cylinder 63a Niji cylinder shaft 65 Niji slide head 66: Lock nut 68: Transport box
69: Grip cylinder 70: Extrusion bar (pressing member) 71: Elastic body 72: Washer 73 = Gear 75: Detection plate 76: Guide pin 77: Coil spring 78: Air piping 79: Nozzle 80: Air cylinder 80a Niji cylinder shaft 82 ; 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 220: Bobbin case transport mechanism (carrying mechanism) ARI~A
R6: Arrow Ml, M2. M3 varnish chipping motor (drive means) S
LI, SL2. SL3. SL4: Solenoid SL, S
2. S5: Proximity sensor S3: Distance sensor S4. S6: Transmissive optical sensor SWI: Mode switch CPU: Microcomputer (electronic control means) CMP
:Analog Comparator Patent Applicant Director of the Agency of Industrial Science and Technology Todoroki Tatsusuke 〉 East 12d map Broom 13a Ward ql East 13b diagram 92 92a

Claims (5)

[Claims] (1) A bobbin case equipped with a bobbin wound with thread; an inner hook equipped with a through hole in the direction of the rotational axis, the diameter of which at least partially matches the outer diameter of the bobbin case; an outer diameter of the inner hook; an outer hook that is provided with a through hole in the direction of the rotational axis, the diameters of at least some of which are substantially the same, and that rotatably supports the inner hook within the through hole; a support member that rotatably supports the outer hook; retaining means for retaining at least one bobbin case;
A carry-in mechanism comprising a pressing member that moves in a direction that substantially coincides with the axis of the through hole of the inner pot;
A nozzle that blows gas into the through hole of the inner pot from the carry-in mechanism side; A driving means for driving the pressing member; and when a predetermined instruction is given, the driving means is controlled to move at least one bobbin case into the inner pot. An automatic bobbin thread supply device for a sewing machine, comprising: an electronic control means for pushing the bobbin case toward the inner pot, pushing out a bobbin case in the inner pot, and inserting another bobbin case into the inner pot. (2) The automatic bobbin thread supply device for a sewing machine according to claim 1, wherein the holding means of the carry-in mechanism has a cylindrical shape, and the nozzle is opened inside the cylinder of the holding means. (3) The nozzle is provided with a solenoid valve for controlling gas blowout, and the electronic control means prohibits the gas blowout from the nozzle except when replacing the bobbin case. The automatic bobbin thread supply device for the sewing machine described in Section 1. (4) The electronic control means is equipped with a bobbin thread remaining amount detecting means, and when a predetermined sewing process is completed and a thread trimming operation is performed, the electronic control means detects the remaining bobbin thread amount, and if the result shows that the remaining bobbin thread amount is low, the device automatically detects the bobbin thread remaining amount. Claim No. 1 (1) in which the bobbin case is replaced with
) Automatic bobbin thread supply device for the sewing machine described in item ). (5) The bobbin thread remaining amount detection means includes an actuator that moves in the axial direction near the inner hook and a detection means that detects the moving position of the actuator, and the bobbin installed in the bobbin case is Claim No. (4), wherein the thread is wound at a position that can be expanded and contracted and that restricts the expansion and contraction.
The automatic bobbin thread supply device for the sewing machine described in Section 1.