JPH06210088A - Automatic bobbin case replacing device of sewing machine - Google Patents

Abstract

PURPOSE:To stably mount and remove a bobbin case in and from a bobbin case holder of a sewing machine by a method wherein the bobbin case is mounted and removed with a lever of the bobbin case held by a pair of latch claws. CONSTITUTION:When an empty bobbin is taken out of a sewing machine main body 20, a lever opening device 8 is placed right in front of a bobbin case 4 mounted in a bobbin case holder 21 by front and rear cylinders. Next, a chuck cylinder 1 is driven to slide a latch claw rack 35 toward the left along the lower edge of a stationary latch claw 38 and move the latch 35 toward the right by gears 33 and 34. Thereby, a transfer latch claw 36 is moved toward the right, that causes a lever 25 to be opened, a lock plate 29 to be slid and unlocked from a central pin 26 and a bobbin 27 to be locked with a hook 29a of the lock plate 19. Then, the lever opening device 8 is moved away from the main body 20 and the bobbin case 4 is detached as it held by the lever 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic bobbin case changing device for incorporating a lower thread bobbin in an industrial sewing machine.

[0002]

2. Description of the Related Art Conventionally, bobbin bobbins for industrial sewing machines have been
Due to the sewing function of the sewing machine, there is no choice but to downsize the machine.
It needs to be replaced every 5 minutes. Since the time to replace the bobbin case is lost time, it has been desired to shorten the time to replace the bobbin case. On the other hand, in a sewing factory, one worker often operates a plurality of industrial sewing machines, and in order to improve the operating efficiency of each industrial sewing machine,
An automatic bobbin case changer is used. Also,
An automatic bobbin case changer for the sewing machine is used to keep the sewing machine operating during breaks such as lunch.

For example, in Japanese Examined Patent Publication No. 62-1745, Japanese Examined Patent Publication No. 62-1748 and Japanese Examined Patent Publication No. 62-1749, a plurality of bobbin cases are held in the direction of the sewing machine body of the inner hook, and the bobbin cases are sequentially arranged. A bobbin case automatic changing device for a sewing machine has been proposed in which a bobbin case is fed out and a used bobbin case is pushed out by a new bobbin case to supply the bobbin case to the inner hook. However, since the inventions described in these publications use an inner hook having a through hole at the center and a bobbin case of a special shape, it is necessary to drastically modify the existing industrial sewing machine, and the cost is reduced. There was a problem in practice because it took time.

On the other hand, there is a device that can automatically replace a bobbin case simply by attaching a sewing machine bobbin case automatic changing device to an existing industrial sewing machine without drastically modifying the existing industrial sewing machine. No. 59-49829. In this device, an operating piece whose tip is inclined from the front direction of the bobbin case is directly acted on the lock plate, the lock plate is slid to release the lock, and the bobbin case is attracted by the electromagnet to attract the bobbin case. It is to be removed and attached. The newly wound bobbin case is supplied by a rotary cassette holder that has six holders around it.

[0005] Further, it is possible to easily replace the bobbin case automatically by simply attaching an automatic bobbin case changing device of the sewing machine to the existing industrial sewing machine without significantly modifying the existing industrial sewing machine. As a thing, actual Kaihei 3
JP-A-49072 discloses that a lever, which is held rotatably around a support shaft for sliding a lock plate by an operation plate engaging claw, operates laterally to open the lever and unlock the lock. Then, there is proposed a method in which the bobbin case is moved in the front direction in this state, and the bobbin case is removed and dropped. The newly wound bobbin case is supplied by the cassette in a state where the bobbin cases are stacked and aligned in the front direction.

[0006]

However, the conventional bobbin case automatic changing device for a sewing machine has the following problems. (1) Of the devices that can be used by simply using the existing industrial sewing machine and installing the bobbin case automatic changing device of the sewing machine, in the device in which the lock plate is slid directly by the operating claw, the front face of the bobbin case is attached to the lock plate. Since a strong force acts from the direction, the lock plate may be damaged by repeated use. Further, in the device that unlocks the lever by opening the lever with the operation plate engaging claw, a strong force acts on the lever in the lateral direction of the bobbin case, so there is a problem that the lever is damaged by repeated use.

(2) In an apparatus for holding a bobbin case with an electromagnet, there is a limit to strengthening the force of the electromagnet due to restrictions such as space, and the operating claw that slides the lock plate holds the bobbin case in the electromagnet. There is a case where the bobbin case cannot be removed due to a failure in attracting the bobbin case with the electromagnet because it acts in the direction of removing the bobbin case. Further, in the device for opening the lever by the operation plate engagement claw, the operation plate engagement claw pushes the lever when the lever is opened, whereby the entire bobbin case is tilted and the lock plate that locks the bobbin to the bobbin case is locked. There was a problem that the bobbin remained in the inner hook when the bobbin case came off and the bobbin case was removed from the inner hook.

An object of the present invention is to allow an existing industrial sewing machine to be used as it is by simply incorporating another device, and to prevent the bobbin case from being damaged even if the industrial sewing machine is repeatedly used in operation. (EN) Provided is an automatic bobbin case changing device for a sewing machine, which can stably remove or attach a bobbin case from an inner hook, and which enables an industrial sewing machine to operate even during a break time of an operator.

[0009]

To achieve this object, a bobbin case automatic changing device for a sewing machine according to the present invention has a center inserted into a hollow hole formed in the center of a bobbin case containing a lower thread bobbin. A bobbin case that includes an inner hook having a pin, a lock plate that engages with the constricted portion of the central pin, and a lever that is rotatably held about a support shaft for sliding the lock plate, An automatic bobbin case changing device for a sewing machine, which removes the bobbin case from the inner hook or attaches the bobbin case to the inner hook, including a pair of latch claws that open the lever and hold the bobbin case at a predetermined angle, and a pair of latch claws. Drive the latch claw of to open the lever,
And the first driving means for holding the bobbin case with the first driving means, the second driving means for moving the pair of latch claws in the axial direction of the central pin, and the second driving means for holding the lever between the pair of latch claws. And the bobbin case is attached to the inner hook.

To achieve this object, the bobbin case automatic changing device for a sewing machine of the present invention includes a central pin fitted in a hollow hole formed in the center of a bobbin case containing a lower thread bobbin. The bobbin case includes a hook, a lock plate that engages with the constricted portion of the central pin, and a lever that is rotatably held about a support shaft for sliding the lock plate. A bobbin case automatic changing device for a sewing machine that removes from a hook or attaches a bobbin case to an inner hook, wherein a lever is opened and a pair of latch claws are held at a predetermined angle with respect to the bobbin case.
A state in which the pair of latch pawls holds the lever by driving the pair of latch pawls to open and sandwich the lever, a first drive means for holding the lever, a second drive means for moving the pair of latch pawls in the axial direction of the central pin. And a control means for removing the bobbin case from the inner hook or attaching the bobbin case to the inner hook by the second drive means, and one of the pair of latch claws forms a predetermined angle when the lever is opened. The other of the pair of latch claws is a fixed claw and enters a gap formed by the closed lever and the bobbin case body to open the lever.

[0011]

The pair of chuck claws of the bobbin case automatic changing device for a sewing machine of the present invention having the above structure can stably hold the bobbin case mounted on the inner hook of the sewing machine main body by chucking the lever. That is, since the moving latch claw, which is one of the chuck claws, has an angle with which the tip of the moving latch claw enters the lower side of the lever with respect to the lever in the closed state, the moving latch claw is The force can be applied in the opening direction of and the lever can be opened smoothly. Further, by opening the lever, the lock plate slides to release the lock with the center pin of the inner hook, and the hook portion of the lock plate locks the bobbin to the bobbin case.

Further, a fixed latch claw, which is one of the chuck claws, is provided corresponding to a position of the support shaft in a state where the lever is opened, and a surface contacting the lever is in a state where the lever is opened. Since the angle is formed, when the lever is opened, the lever is prevented from being excessively opened and the lever is prevented from being unduly applied, so that the lever is not damaged. The second drive means retracts the pair of latch claws while chucking the lever. As a result, the bobbin case and the bobbin can be automatically removed from the inner hook of the sewing machine main body. The removed bobbin case and bobbin are dropped by releasing the chucks of the pair of latch claws.

Next, the pair of latch claws are moved to the cassette position where a plurality of bobbin cassettes are stored, and the bobbin case that is pushed out from the cassette and attracted by the magnet is opened by the pair of latch claws. Chuck. Then, the new bobbin case is attached to the inner hook by returning the sewing machine body to the main body side and performing the operation opposite to that taken out.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A bobbin case automatic changing device for a sewing machine, which is an embodiment of the present invention, will be described in detail below with reference to the drawings. Before explaining the bobbin case automatic changing device of the sewing machine, the structure and function of the bobbin case will be described. FIG. 4A is a sectional view showing the structure of the bobbin case 4 with the bobbin 27 built therein. A hollow cylindrical center tube 46 formed at the center of the bobbin case is inserted into the hollow hole of the bobbin 27 that is hollow and has a disk frame at both ends. Although not shown in the bobbin 27 shown in FIG. 4, a bobbin thread for supplying to the sewing machine is wound around the outer periphery of the cylindrical portion of the bobbin 27. In the center hole of the center tube 46, the inner pot 2
The central pin 26 fixedly mounted on 1 is inserted from the lower side. Near the end of the center pin 26, there is formed a constricted portion 26a having a thin diameter in a circumferential shape.

The bobbin case 4 is in the form of a cylinder with a bottom, one end of which is open, and the front part, which is the bottom, has a through hole formed in the center of the center cylinder 46. A guide groove 47 is formed on the front surface of the bobbin case as shown in FIG. The guide groove 47 has a two-step structure, and the lock plate 29 is slidably fitted in the guide groove 47 guided by the lower step groove. One end of the lock plate 29 is fixed to the support shaft 28 that is slidable by being guided by the lower step groove of the guide groove 47. At the other end of the lock plate 29, a hook portion 29a bent downward in a semi-cylindrical shape is formed. The hook portion 29a engages with the outer peripheral portion of the upper disc frame of the bobbin 27 and locks the bobbin 27 in the bobbin case 4 when the bobbin case 4 is removed from the sewing machine.

A lever 25 is attached above the lock plate on the front of the bobbin case 4 so as to be rotatable around a support shaft 28. A semi-cylindrical notch 25a is formed on the lower side of the end of the lever 25 that is fitted to the support shaft 28.
The notch 25a is in contact with the bobbin pressing spring 31. A bobbin pressing spring 31, which is a leaf spring for urging the bobbin in the direction opposite to the front plate, is fixed inside the front plate of the bobbin case. The bobbin pressing spring 31 contacts the upper disc frame of the bobbin 27 and urges the bobbin 27 downward.

Next, the operation of the bobbin case having the above structure will be described. FIG. 4A shows a state of the bobbin case attached to the sewing machine. The lock plate 29 is biased by a spring (not shown) in a direction to engage with the constricted portion 26a of the central pin 26. As a result, the bobbin case 4 is locked to the inner hook 21. The lever 25 is biased by the spring, and the lever 25 is also stored in the groove in a tilted state. Since the bobbin 27 is pressed against the inner hook 21 by the bobbin pressing spring 31, the bobbin 27 performs the same rotation operation as the inner hook 21 while being attached to the sewing machine.
The lower thread wound around the bobbin 27 is fed and used by the operation of the industrial sewing machine.

Next, the case of removing the bobbin case 4 from the sewing machine will be described. 4B shows the bobbin case 4 in the state where the lever 25 is being opened, and FIG.
The bobbin case 4 with the lever 25 completely opened is shown in FIG. When the lever 25 is rotated around the support shaft 28, the notch 25a of the lever 25 is moved to the bobbin pressing spring 31.
Rotate while touching. With this rotation, the support shaft 28
Is guided by the guide groove 47 and slides to the left. Support shaft 2
8 is stopped at a predetermined position by a stopper provided in the guide groove 47. As the support shaft 28 is stopped, the lever 25 also stops at a predetermined position during rotation. Support shaft 28
Along with the movement of the lock plate 29, the lock plate 29 is guided by the guide groove 47 to move to the left, and the lock plate 29 and the constricted portion 26a of the central pin 26 are disengaged. As a result, the bobbin case 4 can be freely removed from the inner hook 21. At the same time, the hook portion 29a engages with the outer circumference of the upper disc frame of the bobbin 27 to lock the bobbin 27 with respect to the bobbin case 4. Accordingly, even if the bobbin case 4 is removed from the inner hook 21, the bobbin 27 moves integrally with the bobbin case 4.

Next, the overall structure of the bobbin case automatic changing device of the sewing machine will be described. FIG. 2 shows a front view of the bobbin case automatic changing device of the sewing machine, and FIG. 3 shows a side view thereof. The bobbin case 4 is vertically attached to the central portion of FIG.
It is attached to 1. A lever opening / closing device 8 including latch claws 36 and 38 for opening / closing the lever 25 is provided on the front side of the front-rear moving table 45. First, the configuration of the lever opening / closing device 8 which is the main part of the present invention will be described with reference to FIG. FIG. 1 is a HH sectional view of the lever opening / closing device 8 of FIG. 2 seen from above. 1A shows a state in which the lever 25 is open, and FIG. 1B shows a state in which the lever 25 is closed.

In FIG. 1 (b), a position on the front surface of the bobbin case 4 mounted perpendicularly to the inner hook 21 at a position where the support shaft 28 is stopped by a stopper with the lever 25 opened. Corresponding to, a fixed latch claw 38 is attached. Here, the lever 25 of the fixed latch claw 38
The surface contacting with forms an angle when the lever 25 is fully opened with the bobbin case 4 mounted on the inner hook 21. A latch claw rack 35 guided by the lower end surface of the fixed latch claw 38 is slidably attached. A movable latch claw 36 is fixed to the latch claw rack 35 at a position corresponding to the fixed latch claw 38. The surface of the movable latch claw 36 facing the fixed latch claw 38 is formed parallel to the surface of the fixed latch claw 38. Latch claw rack 35
Meshes with the large gear 34. The drive rack 32 meshes with the small gear 33 that is integrally formed with the large gear 34. The drive rack 32 is connected to the rod of the chuck cylinder 1 which is the first drive means, and is driven by the chuck cylinder 1 to be guided and slid by the first guide plate 8a.

Again, referring to FIGS. 2 and 3, the description of the entire structure of the bobbin case automatic changing device of the sewing machine will be continued. Figure 2
At the front-rear moving table 4 attached with the lever opening / closing device 8
Reference numeral 5 is a second drive means, which is connected to the tip of the rod of the front-rear cylinder 2 fixedly mounted on the left-right moving table 7. The front-rear moving table 45 is formed by a guide formed on the left-right moving table 7,
It is slidable in a direction approaching or separating from the bobbin case 4 (referred to as a front-back direction). The front and rear cylinders 2 are provided with a forward movement sensor 40 that detects the state where the rod is protruding by the position of the piston, and a backward movement sensor 39 that detects the state where the rod is inside the cylinder.

The left and right moving table 7 is connected to the tips of the rods of the left and right cylinders 3 which are the third driving means. The third guide plate 9 is fixedly installed on the lower side of the left and right moving table 7,
Is driven by the left and right cylinders 3 and guided by the third guide plate 9 to slide. As a result, the left and right moving base 7 can be moved between the front position of the bobbin case 4 attached to the inner hook 21 of the sewing machine and the front position of the bobbin case 4 at the bobbin take-out port 10 described later. The left and right cylinders 3 have a right sensor 16 for detecting a state in which the left and right moving table 7 is located in front of the bobbin take-out port 10 by the position of the piston.
And a left sensor 15 for detecting a state in which the left and right moving base 7 is positioned in front of the bobbin case 4 mounted on the inner hook 21 of the sewing machine main body 20.

Next, the construction of the supply device for the new bobbin case 4 in which the lower thread is wound will be described. A cassette 6 that holds a plurality of bobbin cases 4 stacked vertically is attached so as to be vertically vertically attachable. The structure of the cassette 6 is shown in FIG. 5A is a partial sectional view, and FIG. 5B is a sectional view taken along AA.
The cassette 6 is manufactured by press-molding a flat plate into a quadrangular prism having an opening slit on one surface. A stopper 44 is formed at one end of the cassette 6 to hold the bobbin case 4. As shown in the figure, the bobbin case 4 has a front surface in contact with the opposite surface of the opening slit, and 10 bobbin cases are stacked and held in the cassette 6 so that the yarn outlet 30 is located in the upper direction.

The cassette 6 is fixed to the main body of the sewing machine 2
It is held by one cassette magnet 23, 24. A bobbin take-out port 10 having an opening in the shape of the bobbin case 4 is attached to the upper portion of the cassette 6. A bobbin magnet 43 for holding the bobbin case 4 is fixed to the center of the bobbin take-out port 10. Cassette magnet 23
A cassette sensor 48 for detecting the presence or absence of the cassette 6 is attached to the upper side of the. A bobbin case sensor 19 for detecting the bobbin case 4 is attached to the upper right of the bobbin take-out port 10.

A chain 11 orbits the sprockets 14 and 12 in correspondence with the center line position of the cassette 6. A bobbin feed roller 13 is attached to one place of the chain 11. The bobbin feed roller 13 enters the cassette 6 without being obstructed by the stopper 44 and pushes up the bobbin case 4. A stepping motor 42 is connected to the rotation shaft of the sprocket 12. Also, the sprocket 12
Bobbin feed roller sensors 17 and 18 for detecting the bobbin feed roller 13 are provided on both sides of the.

Next, the control device of the bobbin case automatic changing device of the sewing machine will be described. First, FIG. 6 is a block diagram showing pneumatic control of the cylinder. Chuck cylinder 1
The air ports on both sides of the piston are connected to the output port of the solenoid valve 58. The air ports on both sides of the piston of the front and rear cylinders 2 are connected to the output port of the solenoid valve 57. The air ports on both sides of the pistons of the left and right cylinders 3 are connected to the output port of the solenoid valve 59. In addition, the solenoid valves 57, 58,
The two influential ports of 59 are connected to the pneumatic pressure source H.

FIG. 7 is a block diagram showing the overall construction of the control device of the bobbin case automatic changing device of the sewing machine. The controller 51 is a CPU, a ROM that stores a control program,
It is composed of a RAM for temporarily storing signals and the like and an input / output interface. The input terminal of the controller 51 has four cylinder sensors 40, 39, 15, 1
6, the bobbin case sensor 19, the bobbin feed roller sensors 17 and 18, the cassette sensor 48, the cassette set button 56, and the sewing machine main body 20 are connected. Further, the output terminal of the controller 51 has a coil of an electromagnetic valve 58 for driving the chuck cylinder 1, a coil of an electromagnetic valve 57 for driving the front and rear cylinders 2, a coil of an electromagnetic valve 59 for driving the left and right cylinders 3, and an alarm lamp 60. The stepping motor 42 and the sewing machine main body 20 are connected.

The operation of the bobbin case automatic changing device of the sewing machine having the above structure will be described. FIG. 8 is a flowchart showing a control program stored in the controller 51. When the bobbin case automatic changing device of the sewing machine is turned on (S1), all outputs are turned off (S2). As a result, since the solenoid valve 58 is off, the chuck cylinder 1 is open. Further, since the solenoid valve 57 is off, the front and rear cylinders 2 cause
The lever opening / closing device 8 is in a retracted position separated from the bobbin case 4. Further, since the solenoid valve 59 is off, the left and right moving base 7 is located in front of the bobbin case 4 attached to the inner hook 21 of the sewing machine body 20 by the left and right cylinder 3.

Next, when the cassette 6 is mounted, the cassette sensor 48 is on (S1
8) Jump to S7. The case where the cassette 6 is not attached will be described later. When the lower thread absence signal 62 from the sewing machine main body 20 is NO, the lower thread absence signal 62 is Y.
The loop is repeated until ES is reached (S7). When the bobbin thread absence signal 62 is YES, the replacement completion signal 63 is turned off to notify the sewing machine main body 20 that the automatic replacement of the bobbin case 4 is started. When the replacement completion signal is turned off, the sewing machine main body 20 stops operating and the bobbin case 4
Wait until the automatic exchange of is completed.

Next, the operation of the automatic bobbin case changing device of the present invention will be described. Operation for removing empty bobbin from sewing machine main body 20 (S9) FIG.
A detailed flowchart is shown in FIG. First, solenoid valve 5
The coil 7 is energized to drive the front and rear cylinders 2 to move the lever opening / closing device 8 to the front position of the bobbin case 4 mounted on the inner hook 21 of the sewing machine body 20, that is, FIG. 1B.
Move it to the position shown in. At this time, it is confirmed that the forward movement sensor 40 is in the ON state (S32). Next, when the coil of the solenoid valve 58 is energized and the chuck cylinder 1 is driven, the moving latch claw 36 moves to the state shown in FIG. That is, the latch claw rack 35 slides leftward while being guided by the lower end surface of the fixed latch claw 38, and slides the latch claw rack 35 rightward via the small gear 33 and the large gear 34. As a result, the moving latch claw 36 moves to the right.

At this time, since the moving latch claw 36 has an angle with which the tip of the moving latch claw 36 enters the lower side of the lever 25 with respect to the lever 25 in the closed state, the moving latch claw 36 is A force can be applied in the opening direction of the lever 25, and the lever 25 can be opened smoothly. Further, by opening the lever 25, the lock plate 29
Slides to release the lock with the central pin 26 of the inner hook 21, and the hook portion 29a of the lock plate 29 causes the bobbin 27 to move.
Is locked in the bobbin case 4. Further, a fixed latch claw 38 is provided at a position corresponding to the position of the support shaft 28 in a state where the lever 25 is opened, and a surface of the fixed latch claw 38 that contacts the lever 25 is opened. Since the angle of the state is formed, when the lever 25 is opened, the lever 2
The lever 5 will not be damaged because the lever 5 will not be opened too much and the lever 25 will not be subjected to excessive force.

Since the chuck cylinder 1 has a short stroke, a cylinder sensor cannot be attached.
After waiting for a predetermined time (S34), the operation of the chuck cylinder 1 is awaited. Next, the solenoid valve 57 is turned off, and the front and rear cylinders 2 separate the lever opening / closing device 8 from the sewing machine main body 20. This state is confirmed by the reverse sensor 39 (S36). As a result, the bobbin case 4 can be taken out from the sewing machine main body 20 while the lever 25 is securely chucked, so that the hook portion 29a of the lock plate 29 can be removed.
The bobbin 27 locks the bobbin 27.
There will be no trouble remaining. Fixed latch claw 3
8 and the movable latch claw 36 chuck the lever 25 and remove it from the inner pot 21, the tip of the movable latch claw 36 contacts the bobbin case 4 to maintain the opening angle between the lever 25 and the bobbin case 4. ing.

Next, the chucked bobbin case 4 is discharged (S10). That is, as shown in FIG.
The solenoid valve 58 is turned off (S41), the moving latch claw 36 is brought into the state of FIG. 1 (b), and the bobbin case 4 is dropped downward. A bag is arranged at the dropping position of the bobbin case 4, and accommodates the bobbin case 4 and the bobbin 27 that are falling. While the bobbin case 4 is being taken out (S9) and the bobbin case 4 is being released (S10), the bobbin inside the cassette is fed (S11) (S1).
1).

The detailed operation of the bobbin feeding (S11) in the cassette is shown in the flow chart of FIG. The stepping motor 42 is driven to drive the sprocket 12 and the chain 1.
The bobbin feed roller 13 is moved upward via 1 (S51). As a result, the bobbin feed roller 13 pushes the bobbin cases 4 stacked in the cassette 6 upward. When the uppermost bobbin case 4 is pushed up to the bobbin take-out port 10 and the bobbin case sensor 19 detects the bobbin case 4 (S52), the stepping motor 42 is stopped (S56). Although the bobbin take-out port 10 is opened in the front direction with respect to the bobbin case 4, since the bobbin magnet 43 attracts the bobbin 27, the bobbin case 4 is held by the bobbin take-out port 10. If no bobbin case 4 remains, the bobbin feed roller 13 passes through the cassette 6 and the bobbin feed roller sensor 18 is turned on (S18),
A bobbin-less signal is set (S54).

Next, the bobbin is taken out (S12).
The details of the bobbin removal (S12) are shown in FIG. The coil of the solenoid valve 59 is energized to move the left and right moving base 7 to the front position of the bobbin take-out port 10 by the left and right cylinders 3 (S61). Then, the operation of the left and right cylinders 3 is confirmed by the right sensor 16 (S62). Next, the coil of the solenoid valve 57 is energized to move the lever opening / closing device 8 to the front of the bobbin case 4 held in the bobbin take-out opening 10 by the forward cylinder 2. Lever opening / closing device 8 at this time
The positional relationship between the bobbin case 4 and the bobbin case 4 is similar to that shown in FIG. The operation of the front and rear cylinders 2 is confirmed by the forward movement sensor 40 (S64).

Next, the coil cylinder of the solenoid valve 58 is de-energized to drive the chuck cylinder 1 to open the lever 25 and chuck the bobbin case 4 (S65). At that time, it stands by for a predetermined time (S66). Next, the coil of the solenoid valve 57 is energized to move the bobbin case 4 by the front and rear cylinders 2.
The lever opening / closing device is moved backward with the chucked state (S67). Check the operation of the front and rear cylinders (S6
8).

Next, the bobbin case is set on the sewing machine main body 20 (S13). The details are shown in the flow chart of FIG. The energization of the coil of the solenoid valve 59 is shut off, and the left and right moving base 7 is moved to the front of the inner hook 21 of the sewing machine body 20 by the left and right cylinders 3 (S71). The left sensor 15 confirms the movement of the left and right cylinders 3 (S72). The coil of the solenoid valve 57 is energized and the front / rear cylinder 2 advances the lever opening / closing device 8 to the front of the inner hook 21 of the sewing machine main body 20 to mount the bobbin case 4 on the inner hook 21. This is confirmed by the forward movement sensor 40 (S75).

At this time, even if a predetermined time has passed (S74),
When the forward movement sensor 40 is not turned on, it is determined that the bobbin case 4 remains in the inner hook 21, and the bobbin remaining trouble is detected (S81). With the bobbin case 4 attached to the inner hook 21, the coil of the solenoid valve 58 is de-energized (S76), and the moving latch claw 36 is moved leftward.
The lever 25 is closed. After a predetermined time has passed (S7
7) The power supply to the coil of the solenoid valve 57 is cut off, and the lever opening / closing device 8 is retracted by the front and rear cylinders (S78).
The operation of the front and rear cylinders 2 is confirmed by the reverse sensor 39 (S79).

Next, when the automatic replacement of the bobbin case 4 is completed (S14), a replacement completion signal 63 is sent to the sewing machine main body 20 (S15). When there is no bobbin in the cassette 6, an alarm is issued (S16), the alarm lamp 60 is turned on, and the buzzer is sounded. Then, the bobbin feed roller 13 is moved to the bobbin feed roller sensor 17 which is the origin position (S3). In that state, the operator sets the cassette 6
Wait to set. The operator sets the cassette 6 (S4) and presses the cassette set button 56 (S
5). As a result, the replacement of the cassette 6 is confirmed (S
6). Further, when a trouble occurs in the bobbin case automatic changing device of the sewing machine, the trouble occurrence signal 64 is sent to the sewing machine main body 20. Bobbin replacement end signal 63
In response to this, the sewing machine main body 20 starts the sewing operation.

As described in detail above, according to the bobbin case automatic changing device for the sewing machine of this embodiment, the lever 25
And a pair of latch claws 36 and 38 for holding the open claw at a predetermined angle with respect to the bobbin case 4, and a pair of latch claws 36 and 38.
The chuck cylinder 1 which drives the lever 25 to open and sandwich the lever 25, the front and rear cylinder 2 which moves the pair of latch claws 36 and 38 in the axial direction of the central pin 26, and the pair of latch claws 36 and 38 sandwich the lever 25. While holding, remove the bobbin case 4 from the inner hook 21 with the front and rear cylinders 2,
Alternatively, since the bobbin case 4 has the controller 51 for mounting it on the inner hook 21, the bobbin case 4 can be detached and mounted while the lever 25 is chucked, so that an unreasonable force does not act on the lever 25. The bobbin 27 and the bobbin case 4 can be surely removed or attached.

The present invention is not limited to the above embodiments, but various modifications can be made. In this embodiment, the air cylinder is used as the driving means for the latch claw, but a driving means such as a motor or a solenoid may be used. Further, in the present embodiment, only a pair of chuck claws are used, but 2
If the bobbin case 4 is removed from the sewing machine main body 20 and the bobbin case 4 is taken out from the bobbin take-out port 10 at the same time using a pair of chuck claws, the bobbin case 4 replacement time can be shortened.

[0042]

As is clear from the above description, even if the existing industrial sewing machine main body is not remodeled, the bobbin case automatic changing device of the sewing machine of the present invention can be added.
Since the bobbin case is removed or installed while the lever of the bobbin case is chucked by the pair of latch claws, the bobbin case can be unlocked with respect to the inner hook and the bobbin can be locked with the bobbin case securely. The hebbin case can be stably supplied, and the operating rate of the industrial sewing machine can be increased.

[Brief description of drawings]

FIG. 1 is a plan view showing a configuration of a lever opening / closing device.

FIG. 2 is a front view showing the overall configuration of an automatic bobbin case changing device for a sewing machine that is an embodiment of the present invention.

FIG. 3 is a side view showing an overall configuration of a bobbin case automatic changing device for a sewing machine that is an embodiment of the present invention.

FIG. 4 is a sectional view showing a configuration of a bobbin case and a bobbin.

FIG. 5 is a cross-sectional view showing a configuration of a cassette.

FIG. 6 is an air circuit diagram for driving a cylinder.

FIG. 7 is a block diagram showing a configuration of a control device of the bobbin case automatic changing device of the sewing machine.

FIG. 8 is a flowchart showing an overall control process of the bobbin case automatic changing device of the sewing machine.

FIG. 9 is a first partial flowchart showing a partial process of control.

FIG. 10 is a second partial flowchart showing a partial process of control.

FIG. 11 is a third partial flowchart showing a partial process of control.

FIG. 12 is a fourth partial flowchart showing a partial process of control.

FIG. 13 is a fifth partial flowchart showing a partial process of control.

FIG. 14 is a sixth partial flowchart showing a partial process of control.

[Explanation of symbols]

 1 chuck cylinder 2 front and rear cylinder 3 left and right cylinder 4 bobbin case 6 cassette 7 left and right moving table 8 lever opening and closing device 10 bobbin take-out port 20 sewing machine body 21 inner hook 36 moving latch claw 38 fixed latch claw

Claims (2)

[Claims] 1. An inner hook having a central pin fitted into a hollow hole formed in the center of a bobbin case containing a bobbin bobbin, a lock plate engaging with a constricted portion of the central pin, and a lock plate slid. A bobbin case having a lever rotatably held about a spindle for moving the bobbin case from the inner hook or attaching the bobbin case to the inner hook. A pair of latch pawls that open the lever and sandwich the lever at a predetermined angle with respect to the bobbin case; a first driving unit that drives the pair of latch pawls to open and sandwich the lever; Second drive means for moving the latch claws of the pair in the axial direction of the central pin, and the bobbin case by the second drive means with the pair of latch claws holding the lever. A bobbin case automatic changing device for a sewing machine, comprising: a control means for removing the bobbin case from the inner hook or attaching the bobbin case to the inner hook. 2. The bobbin case automatic changing device for a sewing machine according to claim 1, wherein one of the pair of latch claws is a fixed claw that forms the predetermined angle when the lever is opened, The other of the latch claws enters the gap formed by the closed lever and the bobbin case body,
An automatic bobbin case changing device for a sewing machine, characterized in that the lever is opened.