JPS61265188A - Sewing machine capable of automatically passing yarn - 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 Field of Industrial Application This invention relates to a sewing machine capable of automatic threading, and more particularly to a threading hook that captures sewing thread supplied to the eye of a sewing needle and inserts it into the eye. In a sewing machine equipped with a threading device having a threading device, the rotating posture of a member that holds sewing thread from a thread supply source and transports it to a threading hook during standby can be corrected to facilitate threading the member. With a simple operation of pressing the operating body, the sewing thread is transferred to the eye of the sewing needle, and the threading hook waiting to be inserted into the eye catches the sewing thread and threads the thread. This invention relates to a sewing machine capable of automatic threading.

In order to sew a workpiece cloth using a conventional sewing machine, as a preparatory work, the sewing thread, which will become the upper thread, is pulled out from the thread spool and passed through various members such as the thread tension plate, thread take-up lever, thread take-up spring body, etc. in a predetermined order and route. It is necessary to hang the needle at the holder and then insert it through the eye of the sewing needle. This need for threading is no exception even in sewing machines equipped with a threading device having a so-called threading hook.

Problems to be Solved by the Invention The threading device equipped with a threading hook, which is suitably adopted in recent sewing machines, simply facilitates the operation of inserting the upper thread into the eye of the sewing needle. It is possible to omit the above-mentioned work of hanging the needle thread on the thread tension disc, thread take-up lever, thread take-up spring body, etc.
It doesn't make this easier. Moreover, the task of threading the upper thread along a predetermined thread supply path is generally an error-prone task for beginners of sewing machines, and is a troublesome task even for experienced users. If the threading is done in the wrong order, the sewing operation cannot be completed even if threading into the eye of the sewing needle is completed, so it is required that the threading be done reliably.

As a device for automatically threading and threading a sewing machine, for example, an invention "Automatic threading device for a sewing machine" proposed by the present applicant is disclosed in Japanese Patent Application Laid-Open No. 59-9509.
Published as number 5.

The disclosed invention is capable of threading the needle thread pulled out from the needle thread supply source onto the thread take-up spring body, as well as threading it through to the eye of the sewing needle, and can be highly evaluated in its own way. be. However, in this device, it is troublesome to wrap the sewing thread pulled out from the thread supply source into the lower end opening of the notch of the manual operating body, and the first operation for transferring the sewing thread downward from the thread take-up is difficult. , and then a second operation for bringing the sewing thread close to the threading hook inserted into the eye of the sewing needle, which poses a problem in ease of operation. Furthermore, the mechanism for transporting the sewing thread was complicated and operational reliability was poor.

OBJECTS OF THE INVENTION The present invention has been proposed in order to suitably solve the problems inherent in the automatic threading device of a sewing machine according to the prior art described above. The position of the member to be transferred to the threading hook is corrected so that it can be easily held by the member, and the operation of transporting the sewing thread to the front of the threading hook, which has been passed through the eye of the sewing needle, is performed by using the operating body. It is an object of the present invention to provide a sewing machine capable of automatic threading, which can be easily achieved by a single movement operation, and which can also simplify the mechanism.

Means for Solving the Problems In order to suitably solve the above-mentioned problems, the present invention provides a sewing needle attached to a needle bar that can reciprocate up and down, and a sewing thread that has been supplied to the eye of the sewing needle by capturing it. a thread holding member having a thread holding end for releasably holding a sewing thread; and a thread holding member having a thread holding end releasably holding a sewing thread; an operating lever that is rotatably provided on the member and pivots the thread holding member at its free end; a first spring means that constantly biases the operating lever toward a predetermined standby position on the sewing machine frame; an operating body movably disposed on the sewing machine frame for rotating the operating lever against the action of the spring means and moving the thread holding member to the eye of the sewing needle; and a second spring means provided at the free end of the actuating lever for constantly biasing the thread holding member to rotate so that the thread holding end portion faces the eye hole of the sewing needle when the thread holding member is moved to the eye hole of the sewing needle; ,
When the operating lever is stopped at a predetermined standby position, a thread holding member is provided to correct the rotational posture of the thread holding end portion to a predetermined rotational posture against the action of the second spring means. The present invention is characterized in that it is provided with an attitude correction member fixedly disposed on the sewing machine frame so as to be engageable with each other.

According to the sewing machine capable of automatic threading according to this configuration, when the operating body is moved in one direction, the thread holding member that releasably holds the sewing thread that will become the upper thread is activated by the operating body. It rotates as the lever rotates, and transports the sewing thread to the eye of the sewing needle.

At this time, the sewing thread of the thread holding member engages with the threading hook inserted into the eye of the sewing needle. Due to the relative movement between the threading hook and the thread holding member, the sewing thread is released from the thread holding member and captured by the threading hook, and then passed through the eye of the sewing needle.

Embodiment Next, a preferred embodiment of the automatic threading sewing machine according to the present invention will be described in detail with reference to the accompanying drawings. Note that FIG. 1 is a front view showing the overall external configuration of a sewing machine incorporating an automatic threading mechanism according to the present invention, and FIG. 2 is a partially cutaway front view showing main parts of the sewing machine shown in FIG. Figure 3 is a plan view of the sewing machine shown in Figure 1, and Figure 4 is the top view of the sewing machine shown in Figure 1.
FIG. 2 is a partially cutaway plan view showing essential parts of the sewing machine shown in the figure. 5 is a cross-sectional view taken along the line 5-5 in FIG. 2, and FIG. 6 is a cross-sectional view taken along the line 6-6 in FIG.

(Basic Structure of Sewing Machine) Particularly in FIG. 1, a sewing machine frame 21 is provided on a base 22, and this sewing machine frame 21 extends horizontally above the base 22 and has a sewing machine on the upper part. Basically, it consists of a lower arm 23 with a processing surface, an upper arm 24 extending in parallel above the lower arm 23 and having a sewing machine head at its tip, and a leg part 25 integrally connecting both arms. It is integrally injection molded from hard synthetic resin to reduce weight. In the sewing machine head of the upper arm 24, as shown in FIGS. 2 and 5, a base frame 26 made of bent steel plate is provided at an appropriate position. A block-shaped needle bar stand 27 is fixed vertically, and a swing frame 29 (hereinafter referred to as "support body") is attached to this needle bar stand 27 via a support shaft 28, with its protrusion 9a,
9b, it is inserted and supported horizontally rotatably (6th
figure). A needle bar 30 is inserted through the support body 29 so as to be able to reciprocate up and down. It is designed to be driven.

A sewing needle 34 having an eyelet 33 for threading the sewing thread formed therein is detachably attached to the lower end of the needle bar 30 via a needle holder 35. Further, a connecting culm 36 shown in FIGS. 4 and 5 is pivotally attached to the support body 29, and by reciprocating the connecting culm 36 in the horizontal direction by a pulse motor (not shown), the connecting culm 36 is moved in a zigzag manner to the needle bar 3o. The lateral rocking motion required for sewing is provided.

(Mainly regarding the threading device) Further, a threading device 38 that functions to capture the sewing system 37 supplied near the eye hole 33 of the sewing needle 34 by a threading hook and pass it through the eye hole 33 is connected to the support body. 29. That is, as is clear from FIGS. 2, 4, and 6, an elongated U-shaped threading guide plate 39 is disposed parallel to the vertical side surface of the support 29, and is pivotally supported by the support body 29 at both end edges thereof so as to be able to pivot around the needle bar 30 by a required angle.

This guide plate 39 has a vertical slit 39a with a predetermined width.
is formed. Further, a threading shaft 40 is inserted into an end extending horizontally from the lower part of the guide plate 39 so as to be movable and rotatable in the axial direction, and a bifurcated member 4 fixed to the needle bar 30
1 holds the threading shaft 40, and the horizontal relative position of the threading shaft 4o with respect to the needle bar 30 is maintained.

A threading slider 42 made of resin and having the shape shown in FIG. 9 is fitted into a slit 39a of the threading guide plate 39 so as to be vertically movable, and the top of the threading shaft 40 is fitted into the upper end of the slider 42. . A guide pin 44 protruding from the threading shaft 40 is inserted into a slot 43 of a predetermined length provided diagonally through the slider 42, and a compression spring 45 shown in FIG.
As a result, the threading shaft 40 is always elastically biased downward. Further, a spring means 46 consisting of a tension spring shown in FIGS. 6 and 7 is engaged between the threading slider 42 and the protruding piece of the guide plate 39, and the slider 42 is always lifted upward by its elasticity. energized. Incidentally, on the side wall of the threading slider 42, an elastic protruding piece 52 that can come into contact with and release from an engaging piece 51 provided on a linking member 50, which will be described later, is branched and protrudes in three directions.

A cylindrical member 47 is inserted into the lower end of the threading shaft 40, as shown in the enlarged plane of FIG. Protective bodies 4.9, 4.9 consisting of tongues extend respectively. The dimensions of this threading hook 48 are as follows:
9, and when the hook 48 is inserted into the eyelet 33 of the sewing needle 34 by the operation of the threading device 38, both protectors 49 hold the sewing needle 34 between them. Protrude more forward. Furthermore, the threading device 3 described above
The basic configuration and operation of No. 8 is described in detail in Japanese Utility Model Application Publication No. 54-43878 filed by the present applicant.

(Regarding the thread supply path of the sewing machine) Next, as shown in FIG. 2, on the sewing machine operator side of the upper arm 24, there is a thread guide member 53 that smoothly guides the sewing thread 37 pulled out from the thread supply source, and a thread tension device. 54. A guide wall 55, a guide body 56, a thread take-up 57, a thread transfer member 58 and a thread holding member 59, which will be described in detail later, are arranged in this order to the left. As shown in the plan view of FIG. 3, the thread guide member 53. The thread insertion portion 54a and the guide wall 55 of the thread tension device 54 form a linear thread supply path extending in the longitudinal direction of the upper arm 24.

Also, the thread guide member 5 guides the sewing thread 37 to the thread tension device 54.
3, the locking portion 5 of the yarn transfer member 58 waiting at a predetermined position.
The thread insertion portion 54a of the thread tension device 54 is set to be oriented in the arrangement direction toward 8a (FIG. 3),
A guide wall 55 that guides the sewing thread 37 into the thread insertion portion 54a
are formed to extend in the arrangement direction of the various members and above the thread insertion portion 54a, respectively. Note that the end surface of the guide wall 55 facing the locking portion 58a of the thread transfer member 58 is bent in the direction of rotation of the thread transfer member 55.

A required recess 60 is formed at the top of the upper arm 24, and the lower half of a thread spool 61, which serves as a thread supply source, is accommodated in this recess. The support rod 62 through which the thread spool 61 is inserted and supported is mounted so as to be biased by a required angle so as to be oriented toward the linear thread supply path.

Furthermore, as shown in FIGS. 3 and 5, the top of the upper arm 24 is provided with a balance 57. A rectangular upper opening 63 is provided to allow the thread transfer member 58 and thread holding member 59 to protrude slightly. Further, as shown in FIGS. 6 and 9, a lower opening 64 is provided in the lower surface of the upper arm 24 to allow passage of the sewing thread 37 and the thread holding member 59.

Since the take-up lever 57 is designed to reciprocate up and down in an arc in the upper arm 24, the front part of the arm 24 has a slit for passing the take-up lever, as seen in conventional sewing machines, as shown in FIG. There is no such thing, so it has a clean appearance.

Further, as shown in FIGS. 9 to 11, a defining means 91 is provided in the sewing machine frame 21 for defining an upper and lower space in front of the needle bar 30 in which a thread holding member 59 (to be described later) moves. As shown in FIG. 2, this defining means 91 extends a distance sufficient to cover the swinging range of the needle bar 30 in the lateral direction, and is fixed to the sewing machine frame 21 in front of the needle bar 30. It consists of a thread tangle prevention plate 92 and a space defining frame 93 that protrudes forward inside the upper arm 24 as shown in FIG. and the thread tangle prevention plate 9
2, the eyelet 33 of the sewing needle 34 is opened by lowering the thread holding member 59.
The suture thread 37 pulled out to the vicinity of is smoothly guided downward, and the thread is prevented from becoming entangled with other members.

(Mainly Regarding the Thread Holding Member) As shown in FIGS. 2 and 6 to 11, a thread holding member 59 that holds the sewing thread 37 in a releasable manner is disposed in the upper arm 24. By operation, the thread holding member 59 can be moved from its standby position to the eye position of the sewing needle 34. That is, a slit 66 of a predetermined length is vertically bored in the left side surface of the upper arm 24 shown in FIG. 2, and a linking member formed by bending a plate material into the shape shown in FIGS. 5o extension end 5
0a faces, and an operating body 65 consisting of a rectangular knob located outside the sewing machine frame 21 is fixed to this end 50a. Further, a holding frame 67 having a shape shown in FIG.
a.

A guide shaft 68 is vertically inserted and fixed between the guide shafts 67b, and the linking member 50 is inserted through the guide shaft 68 so as to be able to move up and down (FIG. 2). As shown in FIG. 6, an elastic body 69 made of a tension spring is stretched between the linking member 50 and the holding frame 67, thereby allowing the linking member 50 and the operating body 6S to be inserted into the slot. It is lifted and biased to the top of 1-66.

As clearly shown in FIG. 7, the needle bar 3 of the linkage member 5o
An actuating lever 71 having the shape shown in the figure is pivotally attached to a position rearward from the fixed shaft 70, and the fixed shaft 7
As shown in FIG.
It is designed to be constantly lifted and biased to a predetermined standby position shown in the figure.

Note that the operating lever 71 is connected to the needle bar 3 as shown in FIG.
It is rotatable by a required angle around the axis of the fixed shaft 70 that is substantially perpendicular to
It is supported so that a thread holding member 59, which will be described later, is located in FIG. 1).

A thread holding member 59 (described later with reference to FIGS. 13 and 14) that releasably holds the sewing thread 37 is rotatably provided at the free end of the operating lever 71 via a shaft pin 73. There is. The opposite end 71a of the operating lever 71 extends a predetermined distance rearward from the fixed shaft 70, and can come into contact with a cam surface 74a shown by a broken line of the control cam 74 shown in FIG. 7 when a predetermined tilt angle is reached. The dimensions are set to . The control cam 74 is disposed within the upper arm 24 so as to be formed along the operating direction of the operating body 65, and rotates the operating lever 71 in response to the operating position that changes as the operating body 65 moves up and down. It functions to control posture. Further, in the downwardly extending portion of the cam surface 74a, as shown in FIGS.
As will be described with reference to FIG. 11, while the thread holding member 59 is moved to a position close to the sewing needle 34 and is located within a predetermined range in the vertical direction centering on the eye hole 33, the operating lever 71 is rotated. Linear holding cam surface 7 that maintains a constant moving posture
4b is also formed. Further, as shown in FIG. 6, a cam protrusion 74c having the shape shown in the figure is formed to protrude from the control cam 74, and when the operating lever 71 is urged upward by the first spring means 72, the control cam 74 is pressed against the fixed shaft 70. The base end 71b of the supported operating lever 71 is connected to the cam protrusion 74.
It is stably held in its standby position by contacting the slope of c.

By pushing down the operating body 65 connected thereto outside the sewing machine frame, the linking member 50 inserted through the guide shaft 68 is moved a predetermined distance along with the actuating lever 71 against the elasticity of the elastic member 16 69. However, as shown in FIG. 7, the other end 71a of the operating lever 71 comes into contact with the cam surface 74a of the control cam 74, and the operating lever 71 follows this and lowers the fixed shaft 70.
It can be rotated clockwise with respect to the linking member 50 and the operating body 65 at a required timing.

Next, as shown in FIGS. 13 and 14, the thread holding member 59 is rotatably attached to the lock-shaped free end of the operating lever 71 via a shaft pin 73. . This thread holding member 59 has a thread holding end 75 for holding the sewing thread.
a (hereinafter referred to as a "fixed end") and is pivotally supported on the free end of the lever 51, and a compression spring shown in FIG. 76, and a movable body 77 elastically biased toward the fixed end 75a.

The movable body 77 is formed with a thread holding end 77a (hereinafter referred to as a "movable end") for holding a sewing thread that can be engaged with and disengaged from the fixed end 75a of the base body 75.

Further, as shown in FIG. 13, the fixed end 75 of the base body 75
A is provided with a first recess 78 that allows both the threading hook 48 and the protector 49 to enter, and the movable body 7
A second V-shaped recess 79, which is narrower than the first recess and allows only the threading hook 48 to enter therein, is bored in the movable end 77a of the second V-shaped recess 79. The dimensional relationship between the first recess 78 and the second recess 79 is such that the thread holding member 59 reaches the position of the eye hole 33 of the sewing needle 34 and the sewing thread 37 is captured by the threading hook 48, as will be described later. This is necessary in order to automatically release the sewing thread 37 from the thread holding member 59 when carrying out this procedure.

At the pivot point between the thread holding member 59 and the operating lever 71,
As shown in FIG. 13, a second spring means 8 consisting of a torsion compression spring is provided between both ends of the shaft pin 73 and the base body 75.
0.80 (hereinafter referred to as "elastic body") is inserted.

The thread holding member 59 is held by the shaft pin 7 by both elastic bodies 80.
3 is constantly elastically biased in the direction of swing of the needle bar 30,
The first and second recesses 78 and 79 of the thread holding member 59 are located corresponding to the center position of the needle bar 30 in a range in which it can swing in the lateral direction. Also, the thread holding member 59
is pivoted on the free end of the actuating lever 71 so that when it moves near the guide 33 of the sewing needle 34 as shown in FIG. , is constantly urged to rotate by the elastic body 80.

By configuring the thread holding member 59 and the operating lever 71 that pivotally supports it in this manner, when the operating body 65 is manually pushed down, the linking member 50 is guided by the guide shaft 68 and lowered. At this time, the other end 71a of the lever 71 follows the cam protrusion 54c as shown in FIG.
Rotates around the center. As the linking member 50 further descends, the thread holding member 59 holds the sewing needle 34 as shown in FIG.
is moved to the vicinity of the eye hole 33. Note that when the other end 71a reaches the linear holding cam surface 74b, as shown in FIGS.
As shown in the figure, the thread holding member 59 descends while maintaining a constant rotational posture.

(Regarding Thread Transfer Member) Next, as shown in FIGS. 2 and 5, a guide body 56 having an arc-shaped guide surface 56a is vertically arranged and fixed in the sewing machine frame 21, and the guide body 56 is A thread transfer member 58, which will be described later, rotates in the vicinity. Therefore, the arcuate shape of the guide surface 56a is set to match the rotation locus of the thread transfer member 58, and is located at a predetermined point located on the right side of the guide body 56 (in FIG. 2) and below. A known thread take-up spring body 82 is fixed.

The thread transfer member 58 transports the sewing thread 37 held by the thread take-up 57.
It is arranged so as to be rotatable around a fixed shaft 83 located within the sewing machine frame 21 at a predetermined timing in order to transfer the thread to a thread take-up spring body 82 provided on the guide body 56. As shown in FIGS. 7 and 8, the linking member 50
The system transfer member 58 is biased by a first connection control means provided relationally between the system transfer member 58 and the system transfer member 58 . The thread transfer member 58 has a lever shape as shown in FIG. 5, and is pivotally supported on both protruding ends of a fixed shaft 83 that is horizontally inserted and fixed behind the needle bar stand 27 shown in FIG. , from the standby position shown in FIG. 5 to the thread take-up spring body 8 as shown in FIG.
It is possible to rotate to a position below 2. Further, as shown in FIG. 4, a spring means 84 consisting of a torsion spring is attached to the fixed shaft 83 of the thread transfer member 58, and is mounted between the holding frame 67 and the base of the thread transfer member 58. There is.

The spring means 84 causes the locking portion 58a (described later) of the thread transfer member 58 to be kept upward so as to be at a predetermined standby position above the uppermost position of the thread take-up lever 57, as shown in FIGS. 5 and 12. It is elastically biased towards. As is clear from FIG. 8(a), the fixed shaft 83 is arranged behind the needle bar 30 in the sewing machine frame 21, and the thread transfer member 58 moves the needle bar 30 as shown in FIG. It extends forward of the sewing machine through a gap between the supporting body 29 and the needle bar crank 31 that transmits the rotation of the main shaft 32 of the sewing machine.

A locking portion 58a is integrally provided at the upper free end of the yarn diameter feeding member 58, and as can be seen from FIGS. 2, 3, and 12, the locking portion 58a is It is bent into a shape that allows it to pass beyond the tip of the thread take-up 57 and enter between the thread take-up 57 and the thread tension device 54 .

(First connection control member that controls the yarn diameter feeding member) The element transfer member 58 is operated by manually pushing down the operating body 65, after the yarn holding member 59 first starts rotating, as described below. It is rotated with a predetermined time delay by the first connection control member. That is, Fig. 4,
Figure 7.

As shown in FIG. 8(a) and FIG. 15, the thread diameter feeding member 5
A connecting piece 85 having the shape shown in the figure is inserted into the fixed shaft 83 of the pivot portion 8, and is always elastically biased downward by a torsion spring 86. However, the 15th
As shown in the figure, the pivot end portion of the yarn diameter feeding member 58 is bent into the shape shown, and the bent end portion 58b extends below and supports the connecting piece 85. Further, the linking member 5
0 is integrally formed with an engaging piece 50b as shown in the figure, and this engaging piece 50b comes into contact with the connecting piece 85 and presses it downward as the connecting member 50 descends. There is. In this specification, the engagement piece 50b and the connection piece 85 are collectively referred to as a first connection control member.

The connection piece 85 forming a part of the first connection control member
is pivoted on a fixed shaft 83 so that it can move in and out of the vertical movement locus of the other engaging piece 50b. Then, at the timing when the operating body 65 is operated downward and passes a predetermined operating position, the connecting piece 85 connects the connecting member 50.
In response to the pressing force from the engaging piece 50b, the thread diameter feeding member 58
The engagement piece 50b rotates integrally with the engagement piece 50b and retreats from the movement trajectory of the engagement piece 50b. Further, in the upward operation of the operating body 65, the thread diameter feeding member 58 has already returned to the predetermined standby position, and at this time, the connecting piece 85 engages with the engagement piece 50b, so that the thread diameter feeding member 58
8, and retreats from the locus of movement of the engaging piece 50b as the operating body 65 is operated upward.

In this way, the first connection control member is connected to the thread diameter feeding member 58 in the entire range or a part of the operation area of the operating body 65 up to the predetermined operating position where the thread threading on the thread take-up spring body 82 is completed. It functions to connect the operating body 65 (and the linking member 50) and to interrupt the connection between the thread diameter feeding member 58 and the operating body 65 in connection with the operation of the operating body 65 beyond the predetermined operating position. .

(About the thread take-up) As shown in FIG. 12, the take-up thread 57 that pulls up the sewing thread 37 is curved at its tip to form a thread holding hole 57a. An elastic tongue piece 87 is provided for prevention. This balance 57 is the fifth
As shown in the figure, the link is connected to a link (not shown) pivotally supported on a shaft 88 on the base frame 26 in the sewing machine frame 21, and is also connected to the needle bar crank 31 to provide a predetermined reciprocating motion. This is a well-known formula. Note that when the balance 57 reaches the uppermost position, the balance 57 slightly extends outward from the upper opening 63 provided in the upper arm 24.

(Second connection control means for energizing the threading device) The threading device 38 mentioned above is provided with a second connection control means for operating the device in a temporal manner by the downward movement of the connection member 5o. There is. That is, an engagement piece 51 having a shape as shown in FIGS. 2 and 7 is rotatably supported on the linkage member 50, and is always directed upward by a torsion spring 90 wound around the engagement piece 51. In Figure 7, it is biased clockwise. Further, an elastic projecting piece 52 branched from the threading slider 52 is located on a vertical trajectory drawn when the engaging piece 51 descends together with the linking member 5o by pushing down the operating body 65.

As shown in FIG. 7, this elastic protruding piece 52
When the actuating lever 71 starts to rotate when the pressing down of the engagement piece 51 starts, and the yarn diameter feeding member 58 starts to rotate under the action of the first connection control means described above, the engaging piece 51
I have not had contact with him yet. However, when the operating body 65 is further lowered as shown in FIG. 8, the engaging piece 51 comes into contact with the elastic protruding piece 52, causing the threading slider 52 to descend along the guide plate 39 as shown in FIG. Threading hook 48
When the hook 48 is at the same position in the vertical direction as the eye hole 33 of the sewing needle 34, the hook 48 is rotated and inserted into the eye hole 33 of the sewing needle 34.

Note that even after the hook 48 is inserted into the eye hole 33, the operating body 65 is lowered, but as shown in FIG. Only the joining piece 51 is allowed to descend.

When the elastic projecting piece 52 separates from the engaging piece 51, the threading slider 52 rises under the tension of the spring means 46, whereby the threading hook 58 first retreats from the eye hole 33 and then returns to its original position. Rise to the position and return (11th
figure). Therefore, when the operating body 65 returns to its upward position after completing a series of linked operations, the engaging piece 51 comes into contact with the elastic protruding piece 52 which has already returned to its original position. Since it rotates slightly counterclockwise against the elasticity of the torsion spring 90 and deviates from the elastic protruding piece 52, the smooth upward movement of the operating body 65 is not impaired.

That is, the second connection control member consists of an engagement piece 51 and an elastic protrusion piece 52 provided on the linkage member 50, and operates the operating body 65 to insert the threading hook 48 into the eye hole 33, and also inserts the threading hook 48 into the eye hole 33. The threading hook 48 and the operating body 65 are connected in the entire section or a part of the operating area which is a predetermined operating position until the member 59 reaches the eye hole 33, and the operating body 65 exceeds the predetermined operating position. It functions to disconnect the threading hook 48 and the operating body 65 in connection with the operation.

(Other Ancillary Structures) As shown in FIGS. 4 and 6, an operating lever 71 having a thread holding member 59 at its free end faces the opening 63 provided in the upper arm 24 for threading. During the standby period, the holding end of the thread holding member 59 is
The posture has been corrected so that it always points toward the operator in front of the sewing machine.

That is, when the thread holding member 59 is moved near the eye hole 33 of the sewing needle 34, the thread holding end 75a of the thread holding member 59 is moved to the vicinity of the eye hole 33 of the sewing needle 34.

77a is constantly urged to rotate by the second elastic body 80 so as to face the sewing needle 34. However, if the thread holding member 59 is stopped at the standby position in this biased state, the thread holding ends 75a and 77a will be oriented diagonally downward, making it difficult for the operator to hook the thread. . Therefore, in view of the structure in which when the thread holding member 59 returns to the standby position, the upper end 28a of the support shaft 28 that supports the support body 29, which serves as a swing frame for the needle bar 30, faces near that position (see FIG. and FIG. 4), when the thread holding member 59 is returned to the upper end portion 28
forcibly seat the thread holding member 39 in the second position.
The posture of the sewing machine is corrected so that it is directed toward the operator in front of the sewing machine against the rotation biasing action of the elastic body 8o. That is, the upper end portion 28a of the support shaft 28 functions as a posture correcting member for the thread holding member 59.

A base frame 26 serving as a support plate is bolted to the rear side of the sewing machine frame 21, and a needle bar stand 27 is fixed to this base frame 26, and the support shaft 2 is fixed to the needle bar stand 27.
A support body 29 is pivotally supported via 8. Then, the operating lever 71 with the thread holding member 59 removed, the thread transfer member 58, and the linking member 50 are respectively assembled to the support block consisting of the needle bar base 27 and the support body 29, and are attached to the upper arm 24. It is designed to be a unit that can be easily attached and detached.

(Operating procedure of the sewing machine according to the embodiment) Next, the operating procedure of the sewing machine according to the embodiment configured as described above will be explained. To sew with this sewing machine,
Prior to this, it is necessary to thread the thread. In the standby state before the threading operation, as shown in FIGS. 1, 5, and 6, the thread transfer member 58 and the thread holding member 59 are urged upward by spring means provided respectively, and the top of the arm It slightly protrudes from the upper opening 63 and stops. Note that the thread holding member 59 is attached to the upper end portion 28 of the support shaft 28 as described above.
The thread holding end thereof is directed toward the operator in front of the sewing machine. Also, the locking portion 58a of the thread transfer member 58
As shown in FIG. 12, the balance 57 is waiting at a predetermined position above the balance 57 which is stopped at the uppermost position.

In this state, the sewing thread 37, which will become the upper thread, is pulled out from the thread spool 61 stored in the recessed part 60 provided at the top of the three-way arm 24, passed through the thread guide member 53, the thread tension device 54, and then passed through the upper opening. It is inserted into the thread holding hole 57a of the thread take-up 57 protruding from the thread take-up 63 against the elasticity of the tongue piece 87. At this time, the guide wall 55 interposed between the thread tension device 54 and the locking portion 58a of the thread transfer member 58 extends in the arrangement direction from the thread guide member 53 toward the locking portion 58a in the standby position, as described above. Since the sewing thread 37 is formed in a straight line, the sewing thread 37 is naturally guided into the thread insertion portion 54a of the thread tension device 54 in the thread supply path that reaches the guide wall 55 via the thread guide member 53. Further, after pulling out the sewing thread 37 to the left as shown in FIG. 17, the thread holding member 5
The yarn holding end portions 75a and 77a of 9 are fitted and held against the elasticity of the compression spring 76.

After completing this manual work, the operator operates the operating body 65 located on the left side of the upper arm 24 with his fingers and pushes it down all at once, thereby threading the thread take-up spring body 82 and threading the sewing needle 34. The threading operation up to the eye hole 33 is automatically accomplished.

That is, together with the operating body 65, the linking member 5o is connected to the guide shaft 68.
Then, it begins to descend while being guided by a slit 66 provided on the side wall surface of the arm. As a result, the leading thread holding member 59
The actuating lever 71, which is equipped with
It starts rotating clockwise from the standby position about the fixed shaft 7o, and along with this, both holding ends 75a, 77
The sewing thread 37 held between the threads 37a and 37a is pulled out downward through the thread holding hole 57a of the thread take-up 57.

As shown in FIG. 7, when the operating lever 71 is rotated to a substantially horizontal position, the above-described first connection control means that biases the yarn transfer member 58 starts operating. That is, the engagement piece 50b provided on the linkage member 5o is connected to the thread transfer member 5.
The connecting piece 8 is inserted through and supported by the fixed shaft 83 in the pivot portion of 8.
It comes into contact with 5. For this reason, when the lowering of the linking member 5o further progresses, the linking piece 85 as shown in FIG. 8(a)
is pressed, and the thread transfer member 58 is rotated largely clockwise about the fixed shaft 83 via the connecting piece 85. As a result, the locking portion 58a of the thread transfer member 58, which was located above the thread take-up lever 57 during standby, is able to hold the sewing thread on both sides of the thread holding hole 57a of the thread take-up thread 57, as shown in FIG.
7, the arc-shaped guide surface 5 of the adjacent guide body 56
6a to guide the sewing thread 37 to the thread take-up spring body 82. At this time, the operating lever 71- of the thread holding member 59 is in contact with the cam surface 74a of the control cam 74 and rotated under control, and is in the state shown in FIG. 8(a). Further, when the rotation of the thread transfer member 58 reaches its limit in this way, the threading device 3
8, that is, the engagement piece 51
Then, the elastic protruding piece 52 starts engaging.

When the operating body 65 is further pushed down as shown in FIG.
The engagement piece 50b in the first connection control means disengages from the connection piece 85, and therefore the thread transfer member 58 releases the suture thread 37 to its original state under the elastic return action of the spring means 84. Reverses and returns to standby position. As a result, the sewing thread 37
The guide body 56 is guided by a curved indentation 56b formed at the end of the arc-shaped guide surface 56a, and is finally engaged with the thread take-up spring body 82. Also, the other end 71 of the operating lever 71
a rides on the vertical holding cam surface 74b of the control cam 74, and descends while following this cam surface 74b.
From then on, that rotational posture is maintained.

Further, during the transition from the state shown in FIG. 8(a) to the state shown in FIG. Lower it with 40. When the threading hook 48 is at the same height as the eye hole 33 of the sewing needle 34, the threading hook 48 is guided by the slot 43 provided through the slider 42 and the guide pin 44, and the threading hook 48 is moved to its protective body 49. At the same time, the sewing needle 34 rotates on a horizontal plane, and stops with the sewing needle 34 inserted through the eye hole 33, and waits for the sewing thread 37 to be captured. At this time, the thread holding member 59 is held in a constant rotating posture by the holding cam surface 74b as described above, and both holding ends 75
It is located in the vicinity of the eye hole 33 and above the threading hook 48 with the sewing thread 37 stretched between the thread a and 77a.

From the state shown in FIG. 9, the actuating lever 71 equipped with the thread holding member 59 traces the holding cam surface 74b and further descends while maintaining its rotational posture as the operating body 65 is pushed down. As shown in FIG. 13, the thread holding member 59
The sewing thread 37 stretched between the first recess 78 and the second recess 79 is pressed against the threading hook 48 extending from the eye hole 33 of the sewing needle 34. However, at this point, the thread holding member 59 holds the sewing thread 37 under pressure under the action of the built-in compression spring 76.

Further, as shown in FIG. 10, the threading slider 42 has reached its lowering limit position, and the engaging piece 51 provided on the linking member 50 is in a state where the elastic protruding piece 52 is bent backward. There is. During the transition from the state shown in FIG. 10 to the state shown in FIG. 11, the engagement between the elastic projecting piece 52 of the threading slider 42 and the engagement piece 51 is completely released. A compression spring 4 inserted between the slider 42 and the threading shaft 40
5 and the guiding action of the slot 43 and the guide pin 44, the threading shaft 40 is reversed, and the threading hook 48 is retracted from the eye hole 33 of the sewing needle 34 (at this time, the thread 37 is attached to the hook 48). is hooked, and when the thread holding member 59 releases the thread 37 as described later, the thread 37 is pulled out from the eye hole 33). and slider 4
The threading shaft 40 rises together with the slider 42 under the elastic return action of the spring means 46 engaged between the threading shaft 2 and the holding frame 67.

Further, as shown in FIG. 11, the thread holding member 59 further reaches the lowering limit position while its rotational posture is held by the holding cam surface 74b, but at this time, the thread holding member 59 is inserted into the eye hole 33. At the time of passing in front of the threading hook 48, the movable body 77 of the thread holding member 59 abuts and engages with a part of the threading device 38 (for example, the protector 49), and its movable end 77a touches the base body 75. It detaches from the fixed end 75a and releases the sewing thread 37. More details on this operation = 35
- Specifically, as described above, the second recess 79 of the movable body 77 is formed in a bevel shape narrower than the first recess 78 of the base body 75, and has a size that only allows the threading hook 48 to enter. As shown in FIG. 16(a), the movable body 77 of the thread holding member 59 comes into contact with the protector 49 and is prevented from lowering. However, as described above, since the thread holding member 59 further descends while being held in its rotational position by the holding cam surface 74b, the base body 75 is inevitably separated from the movable body 77 as shown in FIG. 16(b). Then, the holding on the sewing thread 37 is released.

In this state that the thread holding member 59 transfers the sewing thread 37 to the eye hole 33 of the sewing needle 34 and presses it against the threading hook 48, the sewing thread 37 is released by the thread holding member 59 as described above, and at this point When the threading shaft 40 is reversed at , the threading hook 48 is retracted and removed from the eye hole 33 with the sewing thread 37 hooked to its tip. As a result, the sewing thread 37 is inserted into the eye hole 33 of the sewing needle 34 (see FIGS. 11 and 16). Note that threading device 3
8, after reversing its hook 48, said spring means 46
It will rise and return to its original position.

Therefore, the sewing thread 37 which becomes the upper thread is attached to the thread guide member 53 mentioned above.
, the thread is inserted into the eye hole 33 of the sewing needle 34 via the thread insertion portion 54a of the thread tension device 54, the light-retaining spring body 82 provided on the guide body 56, and the thread holding hole 57a of the thread take-up lever 57.
All threading and threading for machine sewing is completed.

After this series of threading is completed, when the manual pressing force on the operating body 65 is released, the linking member 50 is guided by the elastic body 69 to the slit 66 and the guide shaft 68 provided on the left side of the arm. while being raised to a predetermined standby position. Therefore, the operating lever 71 of the thread holding member 59, which is pivotally supported by the linking member 50 via the fixed shaft 70, also
The other end 71a follows the cam surface 74a of the control cam 74, rotates and rises, and finally, as shown in FIG. 6, the base end 71b is brought into stable contact with the cam protrusion 74G. Stop. At this time, the thread holding member 59
3, and is seated on the second end 28a of the support shaft 28 to correct its posture, and the thread holding end 7
5a and 77a are directed toward the front of the sewing machine to wait for the next threading.

In this embodiment, the sewing thread 37 is inserted in advance into the thread holding hole 57a of the thread take-up lever 57 before the thread hooking operation, but instead of this, the tip of the thread take-up is bent into a hook shape, and the thread hook is sometimes The tensioned sewing thread may be automatically captured by the hook when the sewing machine starts operating. Further, in this embodiment, the threading hook 48 is configured to operate in conjunction with the movement of the operating body 65, but the threading hook 48 may be operated separately from the operating body 65. Of course.

Furthermore, instead of the combination of the thread take-up spring body 82 and the thread take-up spring body 82 used in this embodiment, a device having the functions of the thread take-up spring body 82 and the thread take-up spring body 57, for example, JP-A-59-62
The device disclosed in Japanese Patent No. 090 may also be used.

Effects of the Embodiment According to the automatic threading machine according to the embodiment of the present invention, when the sewing thread 37 pulled out from the thread supply source 61 is held by the thread holding member 59, the member rotates in its standby position. Since the posture has been corrected, threading of the sewing thread 37 becomes easy.

In addition, by a simple operation of manually pushing down an operating body 65 provided on the outside of the upper arm 24 of the sewing machine, the sewing thread 37 is hung on the thread take-up spring body 82, and the sewing thread 37 is brought up to the eye hole 33 of the sewing needle 34. The threading hook 48, which is inserted into the eye hole 33 and waiting, captures the sewing thread 37 and retreats, thereby threading and threading the thread in a predetermined order, which conventionally required troublesome effort. This can be done easily.

Further, since the thread transfer member 58, the thread holding member 59, and the linking member 5o that operate these two members in a coordinated manner operate reliably, the sewing thread 37 reaches the eye hole 33 of the sewing needle 34 via the thread take-up spring body 82. Transfer can be achieved reliably. In addition, the thread transfer member 58, the thread holding member 59, and the linking member 50 that operates these members in a linked manner have a simple structure.
It is easy to manufacture and can reduce manufacturing costs.

As described in detail, according to the sewing machine capable of automatically threading the thread according to the present invention, when the sewing thread pulled out from the thread supply source is held by the thread holding member, the rotational posture of the member is corrected in its standby position. Since the sewing thread is oriented toward the operator, threading of the sewing thread becomes easy. In addition, in threading a sewing machine, which conventionally required multiple operations, by a single movement of the operating body, the threading hook reliably captures the sewing thread pulled out from the thread supply source near the eye of the sewing needle. It can be moved to the desired position, making threading work easier. Since the member that operates to transfer the sewing thread is constituted by a rotatable operating lever, the construction is simple and the sewing machine can be easily placed in a narrow space within the sewing machine frame.

[Brief explanation of the drawing]

The drawings show a preferred embodiment of a sewing machine incorporating an automatic threading mechanism according to the present invention, and FIG. Figure 2 is a partially cutaway front view showing the main parts of the sewing machine shown in Figure 1, Figure 3 is a plan view of the sewing machine shown in Figure 1, and Figure 4 is a partially cutaway front view of the sewing machine shown in Figure 1.
5 is a cross-sectional view taken along line 5-5 in FIG. 2, FIG. 6 is a cross-sectional view taken along line 6-6 in FIG. 2, and FIG. , FIG. 8(a) and FIG. 8(b)~
FIG. 11 is a schematic operational diagram illustrating over time a state in which the thread holding member, thread transfer member, and threading device operate with a predetermined time difference via the linking member when the operating body is pressed down; ) The figure is a 2nd arrow view of figure 8 (a),
The figure is a partially enlarged view showing the positional relationship between the thread transfer member and the thread take-up lever in a standby state, and FIG. 13 is a sectional view taken along the line 13-13 in FIG. 14 (a).
14(b) are perspective views showing the schematic structure of the thread holding member, FIG. 15 is a schematic perspective view showing the interrelationship of the connecting pieces provided on the fixed shaft of the thread transferring member, and FIG. 16(a). FIG. 16(b) is a schematic explanatory diagram showing step-by-step the process from when the sewing thread held by the thread holding member comes into contact with the threading hook until the grip is automatically released. FIG. FIG. 7 is an explanatory view schematically showing a state in which the thread transfer member is transporting the thread thread along the guide body to the thread take-up spring body. 21... Sewing machine frame 28... Support shaft 28a/upper end portion 29... Swing frame (support body) 30... Needle bar
33... Eye hole 34... Sewing needle 37...
・Sewing thread 38...Threading device 48...Threading hook 59...Thread holding member 65...Operation body 71...Operating lever 72...Spring means 75a/Thread holding end (fixed end) ) 77a・Thread holding end (movable end) 80...Elastic body

Claims (1)

[Claims] 1. A sewing needle (34) that is attached to the lower end of a needle bar (30) that can reciprocate up and down and has an eye hole (33) through which a sewing thread (37) is inserted; a threading device (38) having a threading hook (48) operable to capture the sewing thread (37) supplied to the eyelet (33) of the threader (34) and pass it through the eyelet (33). In the sewing machine, a thread holding end (75a) releasably holds the sewing thread (37).
, 77a), and an operating lever rotatably provided on the sewing machine frame (21) or a member attached thereto, and pivoting the thread holding member (59) at its free end. (71), and a first spring means (72) that constantly biases the operating lever (71) toward a predetermined standby position on the sewing machine frame (21).
and said actuating lever (
71) to attach the thread holding member (59) to the sewing needle (3).
4) In order to move it to the eye hole (33), remove the sewing machine frame (
21), an operating body (65) disposed so as to be movable;
The thread holding member (59) is connected to the eye (33) of the sewing needle (34).
A free end of the operating lever (71) is attached to the free end of the actuating lever (71) to constantly bias the thread holding member (59) so that the thread holding end (75a, 77a) faces the eye hole (33) when the thread holding member (59) is moved. When the provided second spring means (80) and the operating lever (71) are stopped at a predetermined standby position, the rotational posture of the thread holding end portions (75a, 77a) is controlled by the second spring. An attitude correction member (2) fixedly arranged on the sewing machine frame (21) so as to be engageable with the thread holding member (59) in order to correct the rotational attitude to a predetermined rotational attitude against the action of the means (80).
8, 28a) A sewing machine capable of automatic threading. 2. The posture correction member is a swing frame (29) of the needle bar (30).
2. A sewing machine capable of automatic threading according to claim 1, characterized in that the upper end (28a) of the support shaft (28) supports the upper end (28a) of the support shaft (28).