JP2002292174A - Sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the full insertion of a needle thread cassette 2 into a cassette mounting part 3 as mistakenly done by operators eventually disabling the subsequent threading work and the operation of the needlebar 7 before the needle thread cassette 2 is mounted on the cassette mounting part 3. SOLUTION: A stopper pin 67 is made to stick out in the course of inserting the cassette mounting part 3 to hold the position of the needle thread cassette 2. Under such a condition, when needle threads 24 are applied at a specified location of an automatic threading mechanism 10 to complete the preparation work, the first limit switch 53 is turned on and with the driving of an electromagnetic solenoid 58, the stopper pin is retracted to allow the lowering of the needle thread cassette 2. When the needle thread cassette 2 is pushed in down to the lower end of the cassette mounting part 3, a part 43 to be detected turns on the second limit switch 55 to allow the driving of the needlebar.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing machine in which a needle thread cassette is configured to be detachable, and more particularly, to a sewing machine in which the needle thread cassette is inadvertently mounted or not completely installed. The present invention relates to a configuration of a sewing machine that prevents a sewing needle from being driven.

[0002]

2. Description of the Related Art In a conventional ordinary sewing machine, a balance mechanism and a needle bar drive mechanism driven by a main shaft are arranged in an arm portion.
The balance partially protrudes from the vertical slit in the arm head,
Reciprocate up and down. A thread spool mounting portion (thread stand bar) for the upper thread is provided above the arm portion, and a thread tension device and a thread tension spring are arranged on the front side. The needle bar projects downward from the lower surface of the arm portion. A sewing needle is attached to the lower end of the needle bar, and is configured to move up and down with respect to the needle plate. The presser bar supporting the presser foot for holding the material to be sewn has been configured to be switchable by a lever between a lower position for holding the material to be sewn and a retracting position for retreating upward.

In order to replace the upper thread with a sewing machine having such a configuration, conventionally, a thread spool is mounted on a thread stand, and then the thread end of the upper thread is picked with a finger to form a plurality of thread guides. After passing through the thread tensioner, the thread is further threaded to the threading portion of the balance. Next, the operation of passing the thread through the needle hole had to be performed.

Therefore, the applicant of the present application has disclosed in Japanese Patent Laid-Open No. 7-2
Japanese Patent No. 4173 proposes that an upper thread cassette (cartridge) is removably attached to an upper thread cassette attachment portion formed in the left side surface of the arm head of the sewing machine. In the upper thread cassette, a thread spool is housed in a case, and a slit is formed in a wall of the case so that a thread hooking portion (tip portion) of a balance projecting from the sewing machine main body projects into the case. Is provided with a lever for holding the upper thread to be hooked on the thread hooking section of the balance, and is configured such that when the cassette is mounted on the cassette mounting section, the thread can be hooked regardless of the vertical position of the thread hooking section of the balance. Met.

In US Pat. No. 3,749,039, an upper thread cassette is configured to be detachable from an arm portion.
A sewing machine that can easily perform threading is described. Also in this configuration of the sewing machine, the leading end of the balance protrudes from the cassette mounting portion.

[0006]

Accordingly, the state where the upper thread cassette is not mounted on the cassette mounting section or the operator executes the operation of mounting the upper thread cassette on the cassette mounting section and the thread hooking operation. When the sewing machine is operated (started) carelessly, there is a problem that the user's finger may hit the tip of the balance that moves up and down or the position of the sewing needle.

Some conventional sewing machines have an automatic threading mechanism for automatically passing an upper thread through a thread hole of a sewing needle. When this mechanism is applied to the sewing machine on which the upper thread cassette can be mounted, the upper thread cassette is temporarily stopped at a middle portion of the movable area of the cassette mounting portion, and the thread end pulled out from the upper thread cassette is automatically threaded. After the preparatory work of passing the upper thread cassette to the predetermined position, the automatic threading mechanism is driven in conjunction with the movement of pushing the upper thread cassette to the setting completion position to execute the predetermined upper threading.

However, if the user (operator) accidentally pushes the upper thread cassette to the setting completion position without stopping the upper thread cassette at the halfway position, the above-described automatic threading cannot be performed (operation error). was there.

SUMMARY OF THE INVENTION The present invention has been made to solve these conventional problems, and provides a sewing machine with high safety and a sewing machine in which an operation error of automatic threading is prevented from occurring. It is intended to do so.

[0010]

According to a first aspect of the present invention, there is provided a sewing machine having a cassette mounting portion in which an upper thread cassette is removably mounted, while an automatic sewing machine is provided near a sewing needle. In the sewing machine including the threading means, the cassette mounting portion includes a stopper means for temporarily holding the upper thread cassette in a middle portion of the insertion path, and a release means for releasing the stopper means. It is a thing.

According to a second aspect of the present invention, in the sewing machine according to the first aspect, the stopper means is biased to protrude from the cassette mounting portion by a biasing means to hold the position of the upper thread cassette. And the urging force of the urging means is released by the manual releasing means.

Further, the invention described in claim 3 is the first invention.
5. The sewing machine according to claim 1, wherein the stopper means is configured to be able to protrude and retract with respect to the cassette mounting portion by an electric actuator, and a first detecting means for detecting setting of a thread with respect to the automatic threading means is provided. Control means is provided for controlling the electric actuator to be driven to permit passage of the upper thread cassette in accordance with a signal indicating that the setting of the upper thread has been detected by the detecting means.

[0013] On the other hand, the sewing machine of the invention according to claim 4 is
In a sewing machine provided with a cassette mounting portion to which a needle thread cassette is detachably mounted, and in the vicinity of a sewing needle, an automatic threading means is provided. And a control means for controlling the sewing needle to be prevented from being driven in accordance with a signal indicating the absence or incompleteness of the attachment by the second detection means. It is.

According to a fifth aspect of the present invention, in the sewing machine according to the fourth aspect, the control unit includes the second control unit.
When the detection means detects that the upper thread cassette has not been mounted or is incomplete, it controls the sewing needle to move to the needle vertical position and stop in response to the command signal.

Further, according to a sixth aspect of the present invention, in the sewing machine according to the fourth or fifth aspect, the cassette mounting portion includes a position where the upper thread cassette has been mounted.
A second detecting means for detecting the upper thread cassette is provided.

[0016]

Next, embodiments of the present invention will be described. FIG. 1 is a front view of an electronically controlled sewing machine according to the present invention, FIG. 2A is a front view of a state where a cover of a needle thread cassette is removed, and FIG. 2B is II in FIG. 2A.
FIG. 3 is a sectional view taken along line a-IIa, FIG. 3 is a front view of a main part in a state where the upper thread cassette is inserted to a halfway height of the cassette mounting portion, and FIG.
FIG. 6 is a cross-sectional view of the cassette mounting section taken along line IV-IV in FIG. 1, FIG. 6 is a front view of the main part during the threading operation, and FIG. 9 is a state in which the upper thread cassette is completely set in the cassette mounting section. FIG. 10 is a longitudinal sectional view of the cassette mounting section and the balance mechanism shown in FIG.

In the sewing machine 1 according to the present invention, the upper thread cassette 2 containing the thread spool 27 can be removably mounted on the cassette mounting section 3 at the head of the arm section 6 (arm head). In conjunction with the mounting operation of the cassette 2, the upper thread 24 is threaded on the threading section 26 of the balance 25 and the thread tensioner 9, and further through the automatic threading mechanism 10 as an automatic threading means. The upper thread is passed through the needle hole of the sewing needle 12 safely.

First, the basic structure of the sewing machine 1 is shown in FIG.
Referring to FIG. 3 and FIG.
Is composed of a bed 4, a pillar 5 standing upright on the right end thereof, and an arm 6 extending leftward from the upper end of the pillar 5. The arm portion 6 has a needle bar vertical movement mechanism (not shown) for vertically moving the needle bar 7, and a cassette mounting having a substantially U-shaped recess formed in a plan view in which the front and upper surfaces of the sewing machine 1 are open. Part 3 and a thread hooking part 26 at the tip in the cassette mounting part 3.
There is provided a balance mechanism 8 which moves up and down, a thread tensioner 9 arranged at the lower end side of the cassette mounting section 3, and an automatic threading mechanism 10.

The main shaft 11 disposed in the substantially hollow arm 6 is driven to rotate by a sewing machine motor 90 shown in FIG. 14 (functional block diagram) to drive the needle bar vertical movement mechanism and the balance mechanism 8. It is to let.

Since the needle bar vertical movement mechanism has a conventionally known configuration, a detailed description thereof will be omitted. A balance mechanism 8 is provided adjacent to the needle bar 7 which reciprocates up and down by the needle bar vertical movement mechanism. As shown in FIG. And the needle bar crank 22 is connected so as to rotate in conjunction therewith. A needle bar clamp 23 fixed to the upper and lower portions of the needle bar 7 is connected via the needle bar crank 22. A balance 25 provided on a balance crank 20 swings up and down in conjunction with the rotation of the main shaft 11. At the same time, the needle bar 7 reciprocates up and down. A sewing needle 12 is attached to the lower end of the needle bar 7.

The balance mechanism 8 will be described in more detail. The thread hooking section 26 of the balance 25 draws a substantially circular locus on the vertical back plate 3a (see FIGS. 4 and 13) of the cassette mounting section 3. A long slot 13 which can move up and down is formed (see FIGS. 1, 3 and 9). The thread guide member 15 having a base end suspended from a bracket 14 provided at an upper portion in the arm portion 6 has a shape in which a rod is bent substantially in an arc shape in a side view and turned upward at a lower end to be curved in a U-shape. , Two bars 15a, 1
A thread guide gap 15c having an open upper end is formed between 5b. The thread guide member 15 is made to protrude in the front direction of the arm portion 6 through the long slot hole 13, and the thread hook portion 26 of the balance 25 is connected to the two bar members 1 before and after the thread guide member 15.
It is slidably fitted on the outside of 5a, 15b. The balance 25 is configured to reciprocate up and down in an arc of approximately 90 degrees in a side view as shown in FIG. 10 via a balance crank 20 which is rotated by the driving force of the main shaft 11.

The thread tension plates 9a, 9 before and after the thread tension device 9
The opening / closing operation during b is performed by the cassette mounting unit 3 as described later.
While being interlocked with the movement of pushing the upper thread cassette 2 to the lower end of the presser foot, it is also possible to use an up lever of a presser foot (not shown).

Next, the structure of the upper thread cassette 2 will be described in detail. As shown in FIGS. 1, 2 (a) and 2 (b), a case main body 2a having a vertically long and substantially rectangular shape in a front view and a surface thereof. And a cover 2b that covers the side (front side). The cover 2b can be opened and closed by sliding the cover 2b upward with respect to the case body 2a. Further, the cover 2b is a
It is preferable that the upper thread 24 is formed of a transparent member (transparent resin material) so that the thread color and the consumption state of the upper thread 24 in the thread spool 27 stored in 8 can be observed from the outside.

The thread spool storage section 28 in the case body 2a
And a thread tensioner accommodating portion 29 therebelow, a vertical balance moving area 30 on the right side as viewed from the front, and a vertical thread path 31 on the left side as viewed from the front, and partition walls 32a, 32b, 32c,
It is separated by 32d. A thread vertical bar (not shown) is erected on the upper surface of the horizontal partition wall 32a so that the thread spool 27 can be detachably stored. In the thread tensioner accommodating portion 29 surrounded by the vertical partition walls 32b and 32d,
Notches 34a, 34 are formed in the lower plate and the back plate of case body 2a.
b, and when the upper thread cassette 2 is pushed into the cassette mounting section 3 from above, the thread tensioner accommodating portion 29 is
, And the thread tension device 9 can be moved into the thread tension device accommodating portion 29 through the notches 34a and 34b. On the back plate in the balance moving area 30 of the case main body 2a, a vertically long slit 33 is provided so that the thread guide member 15, the balance 25, and the thread hooking portion 26 of the balance 25 projecting forward from the cassette mounting section 3 face. Notch is formed.

When viewed from the front of the case body 2a, the upper part of the thread spool housing part 28, the lower left corner of the case body 2a which is the lower end of the vertically long thread path 31, the lower right end of the thread tensioner housing part 29, and the balance movement. Round bar-shaped thread guides 35a, 35b, 35 are provided at the lower end of the region 30 (the lower right corner of the case body 2a).
c and 35d are arranged, and the upper thread 24 pulled out from the thread spool 27 is connected to the thread guide pins 35a, 35b, 35c,
It is guided outside through the lower right corner of the case body 2a through 35d (see FIG. 2A). In this case, as shown in FIG. 2 (b), the yarn path 31 is provided with an upwardly open yarn guide groove 36a as first yarn clamping means for preventing yarn entanglement due to yarn twisting of the upper yarn 24. The presser plate 36 and the spring plate 37 are provided so as to pinch the upper thread 24 passing therethrough so as to impart an appropriate passage resistance.

The second thread holding means provided at the lower right corner of the case body 2a is configured as follows. That is, the movable pin 3 on which the thread guide pin 35d is mounted in an orthogonal direction.
8 is slidably supported in a hole between a right side plate 39a of the case main body 2a and an inner side plate 39b parallel to the right side plate 39a, and one end of the movable pin 38 is fixed by a leaf spring 41 having one end engaged with the case main body 2a. The distal end is urged to project outward from the right side plate 39a. A slider (round washer-shaped) 42 is supported by the movable pin 38 so as to be movable in the axial direction of the movable pin 38, and the slider 42 has an inner plate 39b and a thread guide as shown in FIG. It is arranged between the pin 35d. Therefore, an appropriate resistance can be given to the passage of the upper thread 24 between the slider 42 and the thread guide pin 35d. When the upper thread cassette 2 is pushed into the cassette mounting section 3, the movable pin 38 is pushed by the wall of the cassette mounting section 3 and retreats against the urging force of the leaf spring 39, and the pinching force of the upper thread is reduced. It is a configuration to cancel.

The rear plate 40a of the case main body 2a at the position of the thread spool storage portion 28 has an upper portion up to the horizontal partition wall 32a in a rearward arc shape in a plan view so as to accommodate the cylindrical thread spool 27. The rear plate 40b at the location of the thread tensioner accommodating portion 29 is linear, and a rearward step 40c is formed between the rear plate 40a and the rear plate 40b.
Further, a detected part 43 protruding downward is provided at the lower left end of the case body 2a (see FIG. 2B). Further, vertically long guide pieces 44, 44 are integrally provided on the left and right sides on the back side of the case main body 2a, and the upper thread cassette is provided only in the vertical direction along the vertically long guide groove 50 in the cassette mounting portion 3. 2 is detachable.

When the upper thread cassette 2 having such a configuration is inserted from above the cassette mounting section 3, the upper thread cassette 2
Since the lower end of the balance moving area 30 on the right side of is opened, the thread guide member 15, the balance 25, and the thread hooking part 26 protruding forward from the back plate of the cassette mounting part 3 move upward through the slit 33. It enters the yarn cassette 2. In this case, the movable pin 38 is pushed back by the convex portion 3b formed on the side wall surface of the cassette mounting portion 3 and retreats, and the thread guide pin 35d and the slider 4
Since the holding of the upper thread 24 between the upper thread 2 is loosened, the operator pulls the thread end protruding from the lower end of the upper thread cassette 2 largely downward.

In this state, the upper thread cassette 2 is temporarily stopped in the middle of the insertion path by a stopper means described later. On the other hand, when the movable pin 38 is not pushed by the convex portion 3b when the upper thread cassette 2 is inserted, the upper thread 24 is still held.

In this state, the upper thread 24 hooked between the left and right thread guide pins 35c and 35d at the lower end of the balance moving area 30 is engaged with the thread hook 26 (see FIG. 3). As shown in FIG. 6, the thread hooking section 26 relatively moves above the balance moving area 30 as the upper thread cassette 2 moves downward. On the other hand, at the lower left position of the upper thread cassette 2, when the thread tensioner 9 is accommodated in the thread tensioner accommodating portion 29, the upper thread 24 hooked between the left and right thread guide pins 35 b and 35 c receives the thread tensioner. 9 can be hooked (see FIG. 6).

Next, when the upper thread cassette 2 is inserted into the cassette mounting section 3 from above, a stopper means for temporarily holding the position of the upper thread cassette 2 (stopping the insertion) at an intermediate portion of the insertion path. Will be described. In the first embodiment, as shown in FIGS. 3 and 4, a spring (an example of an urging unit) (not shown) is provided from the distal end side of the arm unit 6 toward a space (insertion path) of the cassette mounting unit 3. A) is a stopper pin 57 (an example of an engaging body) which is urged to protrude in the horizontal direction, and is configured so that the stopper pin 57 is retracted (withdrawn) by an electromagnetic solenoid 58 as an example of an electric actuator. It is.
The control for allowing the insertion operation of the upper thread cassette 2 by retracting the stopper pin 57 is performed by detecting that the upper thread 24 is set in the automatic threading mechanism 10 as described later. It is executed by a signal.

The reason is that, in the sewing machine 1 in which the upper thread cassette 2 can be attached to and detached from the cassette mounting section 3 and has the automatic threading mechanism 10, the upper thread cassette reaches a position halfway through the insertion path of the cassette mounting section 3. In the preparation position where the upper thread cassette 2 is inserted, the end of the upper thread 24 pulled out from the upper thread cassette 2 is set in a set state in which the thread is hooked on the thread guide or the like of the automatic threading mechanism 10, and then the upper thread cassette 2 is placed in the cassette. Since the automatic threading mechanism 10 is actuated to perform threading of the sewing needle 12 by an operation of completely pushing the upper thread cassette 2 into the mounting portion 3, the operator (user) mistakenly mounts the upper thread cassette 2 first. If the thread is completely pushed into the section 3, the thread end of the upper thread 24 is not in the set state, so that an error occurs in the automatic threading operation. In order to prevent this operation error, the upper thread cassette 2 is securely held at the intermediate position (preparation position) of the insertion path of the cassette mounting section 3, and in this state, is pulled out from the lower end of the upper thread cassette 2. Pick the upper thread 24 with your finger,
An object of the present invention is to surely perform preparation for automatic threading, in which the upper thread 24 is passed through a predetermined portion of an automatic threading mechanism 10 described later and set at a thread preparation position.

For this reason, after the stopper is temporarily stopped at a halfway position in the cassette mounting section 3 by the stopper means, if it is detected that the upper thread 24 has been set in the automatic threading mechanism 10, the position is held by the stopper means. Is released, and the completion of mounting of the upper thread cassette 2 is permitted.

The first limit switch 53 as an example of first detecting means for detecting that the upper thread 24 has been set in the automatic threading mechanism 10 is provided in the cassette mounting section 3.
Is provided on the lower surface of the arm portion 6 which is below the lower portion. The end of the set upper thread 24 is temporarily locked by a hook-shaped thread hooking section 56 provided at the tip of the arm section (see FIG. 3).

Since the automatic threading mechanism 10 has a conventionally known configuration, the mechanism will be briefly described with reference to FIGS. 3 to 10. The shaft 60 and the slider guide shaft 61 are
A hook holding member 62 made of a synthetic resin is fixed to a lower end of the rotatable threading shaft 60. This hook holding member 62
The upper and lower support portions of the first thread guide member 63 having a U-shape in side view are rotatably supported at positions of the threading shaft 60 corresponding to the upper side and the lower side of the first thread guide member 63. Of the first yarn guide member 63, a vertical connecting wall 6 connecting the upper support portion and the lower support portion.
A thread guide groove 64a for engaging and guiding the upper thread is formed in the notch 4 in a notch shape. A hook mechanism including a threading hook 65, two guide hooks 66a, 66b located on both sides of the hook holding member 62, and a wire-shaped hook spring 67 that passes through these hooks horizontally is fixed to the hook holding member 62. I have.

The hook formed at the tip of the threading hook 65 is inserted into the needle hole 12a of the sewing needle 12 at the time of threading (see FIGS. 7 (c) and 8 (a)). Since the upper thread 24 guided by the guide hooks 66a and 66b is located immediately before the needle hole 12a, the hook mechanism is retracted after the upper thread 24 is hooked at the hook portion (FIG. 8 (b)). 7), the threading shaft 60 rotates clockwise in FIG. 7 (b), and returns from the state of FIG. 7 (b) to the state of FIG. 7 (a). Has been passed through.

The second fixed to the hook holding member 62
The leading end of the yarn guide member 68 is bent downward, and the bent portion functions as a yarn guide portion.
Is disposed on the opposite side of the hook mechanism with respect to the threading shaft 60. In addition, the upper and lower leaf spring dish-shaped thread holding bodies 70 are arranged on the side of the hook holding member 62,
The middle part of the upper thread 24 to be threaded is elastically sandwiched and held (see FIGS. 5, 6, 7 (a) and 7 (b)).

The thread guide passage 71 fixed below and approaching a first limit switch 53 as an example of a first detecting means provided on the lower surface side of the arm portion 6 is provided with the threading shaft 60, the slider guide shaft 61, and the like. Is in the raised position, the thread clamp 70 is configured to approach and communicate with the thread clamp, and the upper thread 24 passes through the thread guide passage 71 via the thread clamp 70 in preparation for threading. At this time (see the state of FIG. 3), the first limit switch 53 can detect that the upper thread 24 is present, in other words, that the upper thread 24 is in a setting completed state for automatic threading. It is configured. At this time, the thread end of the upper thread 24 is cut by a cutting blade provided in the thread hooking portion 56 at the tip of the arm 6.

The upper thread cassette 2 is connected to the cassette mounting section 3
When the threading slider 73 protruding forward from the slit 72 of the back plate of the cassette mounting portion 3 is brought into contact with the step portion 40c of the upper thread cassette 2 and lowered, the lowering is performed. In conjunction with the movement, the threading shaft 60 and the slider guide shaft 61 are lowered via a not-shown interlocking mechanism disposed in the hollow of the arm portion 6 (on the rear side of the cassette mounting portion 3). When only the threading shaft 60 rotates in a predetermined direction, the automatic threading mechanism 10 operates via the link mechanism 69 to change the threading state (see FIG. 7A) from the stored state (standby state). 7 (b) in the forward direction, reversely return to the storage state, and when the upper thread cassette 2 is completely mounted on the cassette mounting section 3 (the push-down operation is completed), the threading shaft 60 And slider guide shaft 61 There is to perform one cycle of the above threading operation of returning to the raised stand-by position.

On the other hand, on the left side of the lower end support plate 51 in the cassette mounting section 3 (left side from the position where the thread tensioner 9 is disposed), when the upper thread cassette 2 is completely mounted,
A detection hole 52 into which the detected portion 43 fits is provided. Below the detection hole 52, the detected portion 43 has been lowered to a predetermined height (the mounting of the upper thread cassette 2 is completed, FIG. 9) is provided on the lower surface of the arm section 6 below the cassette mounting section 3 and the like, as an example of a second detecting means that can detect the second detecting means.

At this time, the movable pin 38 is
The thread guide pin 35d and the slider 42 are pushed in against the urging force by the convex portion 3c formed at the lower portion of the side wall surface of the
Of the upper thread 24 is released to allow the thread to pass during sewing.

This configuration aims at controlling the operation of the sewing needle 12 to be inhibited or blocked until the second mitt switch 55 detects the completion of the mounting of the upper thread cassette 2. When the needle 12 is located at a position other than the position where the needle 12 is on the needle (the position where the needle 12 is at the highest position),
It is preferable that the sewing needle 12 be controlled so as to once descend to the needle lower position and then ascend to stop at the needle upper position. The first detecting means and the second detecting means may use a non-contact type sensor such as an optical sensor in addition to the limit switch.

Next, the control means of the present invention will be described with reference to the functional blocks shown in FIG. The control means of the present invention is an electronic control type control device 80 such as a microcomputer. The CPU 81 for executing control (calculation) includes a ROM (read only memory) 82 storing a control program via a bus, It is connected to a random access memory (RAM) 83 for temporarily storing data and an input / output interface. As shown in FIGS. 1 and 3, the input side interface includes a start / stop key switch 84, a reverse stitch key switch 85, and a needle up / down position key switch 86 arranged on the front surface of the arm shown in FIG.
And a first limit switch 5 as the first detecting means.
3 and a second mitt switch 55 as second detecting means
And a lower thread winding switch 87 and a needle vertical position sensor 88 for detecting the vertical position of the sewing needle 12 (needle bar 7). On the other hand, a pulse motor 89 for adjusting the feed amount by a feed dog, a sewing machine motor 90 for rotating and driving the main shaft 11 and a pulse motor 91 for swinging the sewing needle 12 in the left and right direction are provided on the output interface. An electromagnetic solenoid 58 as an example of an electric actuator for releasing the stopper means is connected to a display device 92 such as a liquid crystal panel for displaying a control state and the like.

Next, the control flow of the control device 80 will be described with reference to the main flowchart shown in FIG.
Subroutine flowchart of the bobbin winding process shown in FIG. 1 and FIG.
This will be described with reference to a subroutine flowchart of the warning process shown in FIG.

First, in the main flowchart, when the power switch 93 is depressed to start the control device 80, initialization processing of various data is executed (S1). Next, the electromagnetic solenoid 58 is turned off, and the stopper pin 57 as the stopper means is projected into the cassette mounting section 3 (S2). Thereby, when the user (operator) inserts the upper thread cassette 2 into the cassette mounting section 3 from above, the lower end of the upper thread cassette 2 comes into contact with the stopper pin 57 and the height position of the upper thread cassette 2 Is temporarily held, and it is possible to prevent the user from completely pushing the upper thread cassette 2 by mistake without performing the setting operation for automatic threading preparation.

Next, ON / OF of the bobbin winding switch 87 is performed.
The F state is determined (S3). When the bobbin is not wound on the bobbin (S3: yes), the routine proceeds to a bobbin winding subroutine shown in FIG. 16 to execute the bobbin winding operation (S3).
4). When the bobbin is wound on the bobbin by the bobbin winding device (S3: no), the second limit switch 55
It is determined whether or not is ON (S5). When the second limit switch 55 is ON (S5: yes), the upper thread cassette 2 has been completely mounted on the cassette mounting section 3 irrespective of whether or not the automatic threading operation has been completed normally. Therefore, normal sewing work of the sewing machine is permitted (S6).

If the second limit switch 55 is off
(S5: no), the upper thread cassette 2 is not mounted on the cassette mounting section 3, or the mounting is not completed. If the operator presses the start / stop key switch 84 carelessly in this state, if the sewing needle 12 moves up and down and the balance 25 moves up and down, it is dangerous. Therefore, the vertical movement of the sewing needle 12 and the balance 25 is prohibited. Execute control. In one example, even if the start / stop key switch 84 is pressed, the driving of the sewing machine motor 90 is prohibited. As another method, the clutch provided at the interlocking portion between the main shaft 11 and the needle bar 7 is disconnected, and the needle bar 7
And driving of the balance 25 is prevented.

When the upper thread cassette 2 is not mounted on the cassette mounting section 3 or the mounting is not completed, it is determined that the upper thread 24 is not threaded through the sewing needle 12. Therefore, preparations for executing threading by the automatic threading mechanism 10 are performed. Since the sewing needle 12 must be at the needle-up position to execute threading, first, as a first step, it is determined by the needle up / down position sensor 88 whether the sewing needle 12 is at the needle-up position (S7). ). When the sewing needle 12 is not at the needle up position (S7: no), it is determined whether or not the operator (user) has pressed the needle up / down position key switch 86 (S8). When the needle up / down position key switch 86 is not pressed (S8: no), a warning process (S9) described below is executed to urge the operator to execute the process, such as displaying a reminder message on the display device 92. I do. If the needle up / down position key switch 86 is pressed (S8: yes), the sewing machine motor 90 is driven and stopped until the sewing needle 12 reaches the needle up position (S10).

Each time the needle up / down position key switch 86 is pressed, the sewing machine motor 90 is driven. When a needle up signal or a needle down signal is output from the needle up / down position sensor 88, the sewing machine motor 90 is stopped. Thus, the sewing needle 12 may be stopped at the needle upper position or the needle lower position. In this case, the stop position when the needle up / down position key switch 86 is pressed by the rotation phase of the main shaft 11 becomes the needle up or needle down. Therefore, the sewing needle 12 can be stopped on the needle by pressing the needle up / down position key switch 86 at most twice. A signal generated by pressing the needle up / down position key switch 86 corresponds to the command signal of claim 5. The command signal includes a signal output automatically in addition to the signal output by the manual operation of the operator as described above. For example, when the operator removes the upper thread cassette 2 from a state in which the upper thread cassette 2 is completely mounted, the second limit switch 55 detects that. That is, a detection signal that detects removal of the upper thread cassette 2 can be used as the command signal. In this case, the upper thread cassette 2
The sewing needle 12 automatically stops at the needle upper position by simply removing the needle. Further, the upper thread cassette 2 is connected to the cassette mounting section 3.
From the second limit switch 55 as a command signal.
The sewing needle 12 may be stopped at the needle upper position. As still another form, another switch may be provided, and the sewing needle 12 may be stopped at the needle-up position by a signal of the switch.

In this way, when it is determined that the sewing needle 12 is at the needle upper position (S7: yes), the setting of the upper thread 24 to the automatic threading mechanism 10 (set to the threading preparation state) is next performed. The first limit switch 53 determines whether or not the operation has been performed (S11). 1st limit switch 53 is O
N, that is, if the setting of the upper thread 24 has been completed (S1
1: yes), the control device 80 turns on the electromagnetic solenoid 68
(S12), the stopper pin 57 is retracted,
The lowering of the upper thread cassette 2 is permitted. Thereby, the normal sewing operation of the sewing machine can be executed thereafter.

If the first limit switch 53 is
F, that is, if the setting of the upper thread 24 is not completed (S11:
no), a warning process (S13) is executed.

Next, in the thread winding process (S4) subroutine, as shown in FIG.
Is turned on (pressed) or not (S20). When the start / stop key switch 84 is ON (S20: yes), the spindle 11 is normally driven by driving the sewing machine motor 90 (S21).
Since the clutch in the middle part is disengaged and only the lower thread winding device is driven, the needle bar 7 and the balance 25 are not driven. When the bobbin winding is completed, the bobbin winding switch 87 is normally turned off. When the operator wants to stop the bobbin winding operation urgently, the start / stop key switch 84, the reverse stitch key switch 8
When one of the key switch 5 and the needle up / down position key switch 86 is depressed (S22: yes), the sewing machine motor 90 stops (Step 23), and the emergency stop of the thread winding operation can be performed.

Next, with reference to the subroutine flowchart of the warning process shown in FIG. 17, following the start of the warning process, the start / stop key switch 84 is pressed (S30: yes) or the reverse stitch key switch 85 is pressed. When the key switch is pressed (S31: yes) or when another key switch, for example, the needle up / down position key switch 86 is pressed (S32: yes), a warning message corresponding to the scene is displayed on the display device 92 (S33). For example, in S9 above, "Please set the upper thread cassette correctly."
Is displayed. In addition, at the position of S13, a warning message "Please pass the upper thread through a predetermined position of the automatic threading" is issued.

FIGS. 11, 12 and 13 show a second embodiment of the stopper means 100. FIG. In this embodiment,
The stopper is manually released, and a guide shaft 102 is protruded from the frame 101 fixed to the side of the cassette mounting portion 3 in the arm portion 6 substantially horizontally in the front direction of the arm portion 6. The guide shaft 102 supports a bearing portion 103a of a stopper operating member 103 so as to be movable back and forth. A biasing means 104 such as a coil spring loosely fitted on the guide shaft 102 pushes the bearing portion 103a forward so that the operating portion 103b at the front end of the stopper operating member 103 projects from the mounting hole in the front wall of the arm portion 6. To be configured. Accordingly, by the urging force of the urging means 104, the engaging claw 105 as an example of an engaging body protruding laterally at the rear end of the stopper operating member 103 is moved to one of the guide grooves 50 in the cassette mounting portion 3. The cassette mounting portion 3 is configured to protrude through a rear corner of the cassette mounting portion 3 through an insertion hole 106 formed in the middle of the upper and lower portions. On the other hand, a locking recess 107 is formed at a corner between the back plate and the right side plate 39a of the case main body 2a of the upper thread cassette 2 at a middle part in the vertical direction of the case main body 2a.

With this configuration, the operator (user)
When the upper thread cassette 2 is inserted from above the cassette mounting portion 3, the upper surface of the engaging claw 105 engages with the upper surface of the locking recess 107 in the middle thereof, and the height position of the upper thread cassette 2 is adjusted. Can hold. In this state, the upper thread 24 is hooked at a predetermined position of the automatic threading mechanism 10 to execute a preparation for threading preparation. Thereafter, when the operator pushes the operation section 103b against the spring force (biasing force) of the biasing means 104,
Engagement claw 1 that retracts integrally with stopper operating member 103
05 can be released from the locking recess 107 and the stopper can be released. Therefore, this configuration corresponds to the manual stopper release means in the present invention (claim 2).

The structure of the stopper means of the present embodiment has a small number of parts and the manual release of the stopper, so that it is not necessary to execute electrical control and the production cost can be reduced. In addition, the engaging claw 10
As shown in FIG. 12, the cross-sectional shape of the upper thread cassette 5 is inclined at the lower surface side, so that when the upper thread cassette 2 is pulled out upward, the upper thread cassette 2 can be smoothly taken out without being caught in the locking recess 107. That is, the engagement claw (engagement body) 105
The upper surface thereof acts as a locking portion for locking the upper thread cassette 2, and the inclined guide surface 105 provided on the lower surface of the engagement claw 105.
a when the upper thread cassette 2 is pulled up,
As a result, the engaging claw 105 itself acts as a release guide for retracting against the urging force.

The present invention is not limited to the above-described embodiment, but can be variously modified. For example,
The second detecting means is provided at the downstream end in the insertion direction of the upper thread cassette 2 in the embodiment, but is not limited to this. That is, the second detection means may be provided on the upstream side in the upper thread cassette insertion direction from the downstream end.

[0058]

As described in detail above, the sewing machine according to the first aspect of the present invention has a cassette mounting portion on which the upper thread cassette is removably mounted, and has an automatic threading means near the sewing needle. In the sewing machine, the cassette mounting portion includes stopper means for temporarily holding the upper thread cassette in a middle portion of the insertion path thereof, and release means for releasing the stopper means. is there.

According to this structure, the upper thread can be pulled out from the upper thread cassette held at the intermediate position of the cassette mounting section, and the preparation setting can be executed for the automatic threading mechanism. Then, after the setting operation is completed, the stopper may be released by the release means, and the upper thread cassette may be completely mounted on the cassette mounting portion. Therefore, it is possible to eliminate the disadvantage that the automatic threading is incomplete due to an operation error by the operator (user).

According to a second aspect of the present invention, in the sewing machine of the first aspect, the stopper means is biased to project from the cassette mounting portion by a biasing means to hold the upper thread cassette in position. And the urging force of the urging means is released by the manual releasing means. According to this configuration, the stopper means is always urged in the protruding direction by the urging means, and only the urging force of the urging means is released by the releasing means. Therefore, the number of parts is small and manual operation is required. Since the stopper is released, there is an effect that it is not necessary to execute electrical control and the manufacturing cost can be reduced.

Further, the invention described in claim 3 is the first invention.
5. The sewing machine according to claim 1, wherein the stopper means is configured to be able to protrude and retract with respect to the cassette mounting portion by an electric actuator, and a first detecting means for detecting setting of a thread with respect to the automatic threading means is provided. Control means is provided for controlling the electric actuator to be driven to permit passage of the upper thread cassette in accordance with a signal indicating that the setting of the upper thread has been detected by the detecting means.
According to this configuration, since the stopper means can be released by setting the thread to the automatic threading means, there is an effect that the trouble of releasing can be saved.

On the other hand, the sewing machine according to the fourth aspect of the present invention
In a sewing machine provided with a cassette mounting portion to which a needle thread cassette is detachably mounted, and in the vicinity of a sewing needle, an automatic threading means is provided. And a control means for controlling the sewing needle to be prevented from being driven in accordance with a signal indicating the absence or incompleteness of the attachment by the second detection means. It is.

Accordingly, it is possible to reliably prevent the needle and the balance from being inadvertently driven while the upper thread cassette is not mounted, during the mounting operation, or during the operation of setting the upper thread in the automatic threading mechanism. This provides an effect that a sewing machine that is safe for the operator can be provided.

According to a fifth aspect of the present invention, in the sewing machine according to the fourth aspect, the control means includes:
When the detection means detects that the upper thread cassette is not mounted or incomplete, the sewing needle is controlled to move to the needle vertical position and stop in response to the command signal, so that the position of the sewing needle is halfway. There is an effect that the subsequent threading operation can be performed quickly without stopping at the position.

According to a sixth aspect of the present invention, in the sewing machine according to the fourth or fifth aspect, the cassette mounting portion is provided with a position at which the upper thread cassette has been mounted.
Since the second detecting means for detecting the upper thread cassette is provided, the completion of the mounting of the upper thread cassette on the cassette mounting portion can be reliably detected by the second detecting means.

[Brief description of the drawings]

FIG. 1 is a front view of a sewing machine according to an embodiment of the present invention.

2A is a front view of the upper thread cassette with a cover removed, and FIG. 2B is a cross-sectional view taken along line IIb-IIb of FIG. 2A.

FIG. 3 is a front view showing a state where the upper thread cassette is held at a position by a stopper means;

FIG. 4 is an enlarged cross-sectional view taken along line IV-IV in FIG.

FIG. 5 is a bottom view of the cassette mounting portion.

FIG. 6 is a front view showing a state in which the upper thread cassette is pushed downward for automatic threading.

7A is a bottom view of a main part of the automatic threading mechanism in a standby state, FIG. 7B is a bottom view of a main part of the automatic threading mechanism in a threading state, and FIG. 7C is a threading hook immediately before threading; It is a principal part enlarged bottom view which shows a state of etc.

8 (a) is a perspective view of a main part showing the state of FIG. 7 (c),
(B) is a perspective view of a main part showing a state in which the upper thread engaged with the threading hook passes through the needle hole, and (c) is a cross-sectional view of the main part in a state where the threading hook after the threading is lifted.

FIG. 9 is a front view showing a state in which the upper thread cassette is completely mounted on the cassette mounting portion.

FIG. 10 is a sectional view taken along line XX of FIG. 9;

FIG. 11 is a front view showing a second embodiment of the stopper means.

12 is a sectional view taken along line XII-XII in FIG.

FIG. 13 is a sectional view taken along line XIII-XIII in FIG. 11;

FIG. 14 is a functional block diagram of a control device.

FIG. 15 is a flowchart of a main routine.

FIG. 16 is a flowchart of a thread winding processing subroutine.

FIG. 17 is a flowchart of a warning processing subroutine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sewing machine 2 Needle thread cassette 3 Cassette mounting part 7 Needle bar 9 Thread tensioner 10 Automatic threading mechanism 11 Main shaft 12 Sewing needle 15 Thread guide member 24 Upper thread 25 Balance 26 Threading part 27 Thread block 35a, 35b, 35c, 35d Thread Guide pin 38 Movable pin 43 Detected part 53 First limit switch 55 Second limit switch 80 Control device 86 Needle up / down position key switch 90 Sewing machine motor

[Procedure amendment]

[Submission date] April 11, 2001 (2001.4.1
1)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG. 15

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hiroshi Kitazawa 15-1 Naeshiro-cho, Mizuho-ku, Nagoya City F-term (reference) 3B150 AA01 CD07 CE02 CE09 CE22 DA02 FJ01 FJ04 GD15 GD25 GE03 JA02 JA07 JA11 LA04 LA82 LA84 LB01 NA80 NB18 NC11 QA06 QA07

Claims (6)

[Claims] 1. A sewing machine comprising: a cassette mounting portion to which an upper thread cassette is removably mounted; and an automatic threading means in the vicinity of a sewing needle. A sewing machine comprising: stopper means for temporarily holding a position in the middle of the insertion path; and release means for releasing the stopper means. 2. The apparatus according to claim 1, wherein said stopper means is urged by said urging means so as to protrude from said cassette mounting portion to hold a position of said upper thread cassette. The sewing machine according to claim 1, wherein the sewing machine is configured to release the power. 3. A first mechanism for detecting the setting of a thread with respect to the automatic threading means, wherein the stopper means is configured to be retractable with respect to the cassette mounting portion by an electric actuator.
Control means for controlling the electric actuator to be driven to permit passage of the upper thread cassette in accordance with a signal indicating that the setting of the upper thread has been detected by the first detecting means. The sewing machine according to claim 1, wherein: 4. A sewing machine comprising: a cassette mounting portion to which an upper thread cassette is removably mounted, and an automatic threading means in the vicinity of a sewing needle; Second detecting means for detecting the presence or absence of or completion of mounting, and control means for controlling so as to prevent driving of the sewing needle in accordance with a signal indicating that the mounting is not completed or not completed by the second detecting means. A sewing machine characterized by the following. 5. The control means, when the second detecting means detects that the upper thread cassette is not mounted or is incomplete, moves the sewing needle to the needle vertical position in response to a command signal and stops the sewing needle. The sewing machine according to claim 4, wherein the sewing is performed. 6. The cassette mounting section according to claim 4, wherein a second detecting means for detecting the upper thread cassette is provided at a mounting completion position of the upper thread cassette. The described sewing machine.