JPH0214878B2 - - Google Patents

Description

Yarn transfer member 58 provided A sewing machine with automatic threading capability.

2. The thread transfer member 58 is bent together with the linking member 50, and a guide member 56 whose locking end 58a is provided close to the movement locus of the thread take-up 57
A sewing machine capable of automatic threading according to claim 1, characterized in that the sewing machine is guided in the vertical direction by.

[Detailed description of the invention]

FIELD OF INDUSTRIAL APPLICATION The present invention relates to a sewing machine capable of automatically threading the thread, and more specifically, the present invention relates to a sewing machine capable of automatically threading the thread. In a sewing machine equipped with a threading device that captures the thread with a hook and inserts it into the eye hole, the sewing thread pulled out from the thread supply source is automatically threaded onto the thread take-up spring body by the simple operation of pressing the operating body. The present invention also relates to a sewing machine capable of automatic threading, in which the sewing thread is transferred to the eye of the sewing needle, is captured by a threading hook that is waiting to be inserted into the eye, and threaded.

Prior Art As a preparatory work for sewing work cloth with a sewing machine, the sewing thread that will become the upper thread is pulled out from the thread spool and applied to various members such as the thread tension plate, thread take-up spring body, and thread take-up lever in a predetermined order and route. It is necessary to hook the sewing thread and then insert the sewing thread into the eye of the sewing needle. The need for this series of threading operations 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, performs the task of simply inserting the upper thread into the eye of the sewing needle instead of manually. However, the above-described series of operations for hanging the upper thread on the thread tension disk, thread take-up spring body, thread take-up lever, etc., is not omitted or facilitated. 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 you make a mistake in the order of threading, you will not be able to carry out the sewing work even if the thread has been threaded through the eye of the sewing needle, so it is essential that this threading is carried out reliably. .

As a device for automatically threading and threading in such a sewing machine, for example, an invention proposed by the applicant, "Automatic threading device for sewing machine"
was published as Japanese Patent Application Laid-Open No. 59-95095.
The disclosed invention is capable of automatically threading the needle thread pulled out from the needle thread supply source onto the thread take-up spring body, and also automatically passing the thread through the eye of the sewing needle, and is highly praised from this point of view. It is possible. However, this device requires a first operation to transport the sewing thread downward from the thread take-up, and a second operation to bring the sewing thread closer to the threading hook inserted into the eye of the sewing needle. However, there was a problem with ease of operation. Furthermore, the mechanism for transporting the sewing thread is complicated and the reliability of operation is also poor.

OBJECTS OF THE INVENTION The present invention has been proposed in view of the above-mentioned drawbacks inherent in sewing machines equipped with threading devices according to the prior art. A threading operation is performed in which the sewing thread is pulled out and threaded onto the thread take-up spring body, and the thread is transferred to the front of the threading hook inserted into the eye of the sewing needle, and the thread is captured by the hook and pulled out from the eye.
This can be easily achieved by a single moving operation of the operating body, and at this time, the suture thread is prevented from being suddenly pulled out from the thread supply source, allowing smooth transfer of the suture thread, and the mechanism is simplified. The present invention aims to provide a sewing machine capable of automatic threading.

Means for Solving the Problems In order to suitably solve the above-mentioned problems, the present invention provides a needle bar that is attached to the lower end of a needle bar that can reciprocate up and down,
A sewing needle with an eyelet through which the sewing thread is inserted, and a sewing thread that is supplied from the thread supply source through the thread tension device, thread take-up spring body, and thread take-up to the eyelet of the sewing needle, and can be operated to catch the sewing thread and pass it through the eyelet. In a sewing machine equipped with a threading device having a threading hook, the thread holding member releasably holds a sewing thread, the thread holding member is supported, and the thread holding member is moved from a predetermined position to at least an eye of a sewing needle. a single operating member disposed on the sewing machine frame capable of vertical movement; a linkage member that links the operation of the operating member with the operation of the operating member; and the balance. a thread having a locking end for locking a suture held in the thread, and fixedly mounted on the linking member to move the locking end to the thread take-up spring body in connection with the operation of the operating body; The present invention is characterized in that it is configured to include a transfer member.

Effect: According to the sewing machine capable of automatic threading according to this configuration, when the operating body is operated to move in one direction, the operating member connected relationally to the linking member connected to the operating body starts to descend. The thread held by the thread holding member supported by the actuating member is pulled out downward. Also, in synchronization with the lowering of the actuating member and with a speed delay, the thread transfer member fixed to the linking member starts lowering, and transfers the sewing thread held or to be held by the thread take-up to its locking end. Guide the thread take-up spring body in the hooked state. Furthermore, the thread holding member holding the sewing thread transfers the sewing thread to the eye of the sewing needle by descending, and engages the thread with a threading hook which is inserted into the eye of the sewing needle and is waiting. The threading hook is then timely reversed to capture the suture and withdraw the hook from the eye of the sewing needle, thereby completing the threading of the eye.

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. 3 is a plan view of the sewing machine shown in FIG. 1, and FIG. 4 is a partially cutaway plan view showing essential parts of the sewing machine shown in FIG. 3. 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 the sewing machine) Especially in FIG. 1, the sewing machine frame 21 is connected to the base 2.
2, and this sewing machine frame 21 is
A lower arm 23 that extends horizontally above the base 22 and has a sewing surface on its upper part; an upper arm 24 that extends parallel to above the lower arm 23 and has a sewing machine head at its tip; and both arms. It basically consists of a pedestal section 25 that integrally connects the two, and is integrally injection molded from hard synthetic resin in order to reduce the 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 support frame 29 is attached to this needle bar stand 27 via a support shaft 28.
The protrusions 29a and 29b are inserted and supported in a horizontally rotatable manner. The needle bar 3 is attached to the support frame 29.
This needle bar 30 is connected to a needle bar crank 31 via a needle bar holder (not shown), and is driven vertically and reciprocally by a sewing machine main shaft 32 shown in FIG. .

A sewing needle 34 having an eye hole 33 for threading the sewing thread is detachably attached to the lower end of the needle bar 30 via a needle holder 35. Further, the support frame 29 has a connecting rod 3 shown in FIGS. 4 and 5.
By reciprocating this connecting rod 36 in the horizontal direction by a pulse motor (not shown), it is possible to give the needle bar 30 the horizontal swinging movement necessary for zigzag stitching. ing.

(Mainly regarding the threading device) Further, a threading device 38 that functions to capture the sewing thread 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 frame 29. are arranged in relation to each other. That is, as is clear from FIGS. 2, 4, and 6,
A threading guide plate 39 formed in an elongated U-shape is disposed along the vertical side surface of the support frame 29, and can be rotated by a required angle around the needle bar 30 at both upper and lower end edges thereof. It is pivotally supported by the support frame 29. A slit 39a is vertically formed in the guide plate 39 with a predetermined width. 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 in the axial direction and rotatable around the axis, and a bifurcated member 41 fixed to the needle bar 30 allows This threading shaft 40 is slidably and stably held.

A resin-made moving member 42 (hereinafter referred to as "threading slider") having the shape shown in FIGS. 9 and 11 is disposed vertically inside the threading guide plate 39 (on the support frame 29 side), It is locked by two bolts 42a, 42a inserted into the slit 39a, and can be moved up and down along the slit 39a. The top of the threading shaft 40 is fitted into the upper end of the slider 42 . Further, the slider 42 has slots 4 in a predetermined pattern.
3 is transparently provided, and a threading shaft 4 is inserted into this slot 43.
A guide pin 44 fixed horizontally at 0 is inserted,
The threading shaft 40 is rotated by the compression spring 45 shown in FIG.
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 39a of the guide plate 39, and its elasticity causes the slider 42 to always move upward. It is biased to lift.
The side wall of the threading slider 42 is provided with a guide member 52 (described later) with which an engaging piece 51 provided on a linking member 50 (described later) engages in a relational manner.

A cylindrical member 47 is inserted into the lower end of the threading shaft 40, as shown in the enlarged plan view of FIG.
Protective bodies 49, 49 each consisting of two tongue pieces extend horizontally between the hooks 48.
The dimensions of this threading hook 48 are set shorter than the dimensions of the protector 49, and when the hook 48 is inserted into the eyelet 33 of the sewing needle 34 by the operation of the threader 38, both the protectors 49 are It protrudes forward from the hook while holding the sewing needle 34 therebetween. The basic structure and operation of this threading device 38 are 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, on the side of the upper arm 24 facing the sewing machine operator, there is a thread guide member 53 that smoothly guides the sewing thread 37 pulled out from the thread supply source 61, as shown in FIG. , thread tension device 54, guide wall 81, guide body 5
6. 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 in a row to the left. As shown in the plane of FIG. 3, the thread guide member 53, the thread insertion portion 54a of the thread tension device 54, and the guide wall 81 form a linear thread supply path extending in the longitudinal direction of the upper arm 24. ing.

Further, the thread insertion portion 54a of the thread tension device 54 is oriented in the arrangement direction from the thread guide member 53 that guides the sewing thread 37 to the thread tension device 54 toward the locking end 58a of the thread transfer member 58 waiting at a predetermined position. (Fig. 4), and this thread insertion part 54a
A guide wall 81 for guiding the sewing thread 37 therein is formed to extend in the arrangement direction of the various members and above the thread insertion member 54a.

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, a rectangular upper opening 63 is provided at the top of the upper arm 24 to allow the thread take-up 57, thread transfer member 58, and thread holding member 59 to protrude slightly. has been done. In addition, on the lower surface of the upper arm 24, there are shown FIGS.
As shown in the figure, a lower opening 64 is provided through which a portion of the sewing thread 37, thread holding member 59, and thread transporting member 58 may pass. Note that the thread take-up lever 57 is designed to reciprocate up and down in an arc in the upper arm 24, so as shown in FIG. It does not exist and therefore has a simple 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. This defining means 91
As shown in FIG.
It consists of a thread tangle prevention plate 92 fixed to the upper arm 24, and a space defining frame 93 projecting forward inside the upper arm 24 as shown in FIG. The thread tangle prevention plate 92 smoothly guides the sewing thread 37 drawn out to the vicinity of the eye hole 33 of the sewing needle 34 downward as the thread holding member 59 descends, and prevents the thread from becoming tangled with other members. .

(Mainly regarding the thread holding member) As shown in Fig. 2 and Figs. 6 to 12,
A thread holding member 59 that releasably holds the sewing thread 37 is disposed inside the upper arm 24, and the thread holding member 59 is moved from its standby position to the eyelet position of the sewing needle 34 by operating the operating body 65. I'm starting to get it. That is, the upper arm 2 shown in FIG.
A slit 66 of a predetermined length is vertically bored in the left side surface of 4, and the protruding piece 50a of the linking member 50 having the shape shown in FIG. 11 faces into this slit 66. A single operating body 65, which is a rectangular knob member located outside the sewing machine frame 21, is fixed to the protruding piece 50a. Further, inside the upper arm 24, there is a holding frame 67 having the shape shown in FIG.
is arranged and fixed, and a guide shaft 68 is vertically inserted and fixed between ends 67a and 67b which protrude horizontally from this holding frame 67 and are vertically opposed to each other. It is inserted freely (FIGS. 2 and 11).

Note that the linking member 50 and the operating body 65 are always lifted and biased to a position above the slit 66, and an elastic body 69 is used for this purpose. For example, an operating member 71, which will be described later, is pivotally supported on the linking member 50 via a fixed shaft 70, and a sixth As shown in the figure, by tensioning the tension spring 69, the linking member 50 and the operating body 65 are biased in the lifting direction.

As clearly shown in FIGS. 6 and 11, an actuating member 71 having the shape shown in the drawing is pivotally attached to a portion of the linking member 50 located rearward of the needle bar 30 via a fixed shaft 70. As shown in FIGS. The actuating member 71, together with the linking member 50, is constantly lifted and biased to a predetermined standby position shown in FIG. 6 under the elastic action of the tension spring 69. The actuating member 71 is rotatable around the fixed shaft 70 within a required angular range, and positions the thread holding member 59, which will be described later, in a plane containing the needle bar 30 (FIGS. 5 to 9). I support it as such.

One free end of the actuating member 71 is bent into a U-shape as shown in FIG. (described later with reference to) is rotatably provided via a shaft pin 73. Further, at the opposite end of the actuating member 71, as shown in FIG. 6 in particular, bifurcated followers 71b and 71c that expand at an angle close to a right angle are integrally formed. The dimensions of the follower 71c are set such that it 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. This control cam 74 is arranged in the upper arm 24 along the operating direction of the operating body 65, and controls the rotational attitude of the operating member 71 in accordance with the operating position that changes as the operating body 65 moves up and down. It functions as expected. Further, in the downwardly extending portion of the cam surface 74a, as will be explained later with reference to FIGS. 9 to 12, a thread holding member 59 is moved to a position close to the sewing needle 34, and the eye hole 33
A linear holding cam surface 74b that maintains the rotational posture of the actuating member 71 constant via the follower 71c while the actuating member 71 is located within a predetermined range in the vertical direction around .
are formed together.

As shown in FIG. 7, the follower 71b comes into contact with a protruding cam surface 74c provided on the control cam 74 when the actuating member 71 is lowered a predetermined distance from its standby position, and the actuating member 71b The function is to rotate the member 71 clockwise relative to the linking member 50. That is, the linking member 50 inserted through the guide shaft 68 moves the operating member 7 against the elasticity of the elastic body 69 by pushing down the operating member 65 connected thereto outside the sewing machine frame.
1 and descend by a predetermined distance. As shown in FIG. 7, the follower 71b of the actuating member 71 contacts and moves along the protruding cam surface 74c of the control cam 74, so that the actuating member 71 moves clockwise around the fixed shaft 70 as required. Rotation with respect to the linking member 50 is started at the timing of .

Next, as shown in FIGS. 10 to 12, the thread holding member 59 is rotatably attached to the U-shaped free end of the operating member 71 via a shaft pin 73. There is. This thread holding member 59 is made of hard resin, and has sewing threads 37 at appropriate locations.
The needle bar 30 is provided with a thread holding end portion that releasably holds the needle bar 30 and is movable in the swinging direction of the needle bar 30 with respect to the actuating member 71. That is, sewing thread 37
The thread holding end that releasably holds the thread holding member 59 includes a protruding piece 59a integrally formed with the thread holding member 59, and a metal elastic piece that is fixed to the thread holding member 59 and protrudes slightly forward of the protruding piece 59a. It consists of 55. As shown in FIG. 10, the thread holding end portion consisting of the projecting piece 59a and the metal elastic piece 55 holds the sewing thread 37 as the operating member 71 rotates.
The sewing thread 37 is brought to the position of the threading hook 48 inserted through the eye hole 33 of the sewing needle 34. At the pivot point between the thread holding member 59 and the actuating member 71, compression springs 80, 80 are attached to shaft pins 73 extending on both sides with the thread holding member 59 in between, as shown in FIG. As a result, the thread holding member 59 is elastically biased on the shaft pin 73 so as to be able to move left and right in the direction in which the needle bar 30 swings.

In the zigzag sewing machine, the needle bar 30 swings within a predetermined angular range, so the stopping position of the needle bar is indefinite. Therefore, even if the thread holding member 59 is lowered under the pressing operation of the operating body 65, the thread holding end portion holding the sewing thread 37 is not necessarily connected to the needle bar 30 and the sewing needle 3.
The stop position shown in FIG. 4 is not necessarily reached. Therefore, in order to guide the thread holding end holding the sewing thread 37 to a position close to the eye hole 33 of the sewing needle 34, a first guide member 52 that can engage with the thread holding member 59 is provided.
As shown in FIGS. 1 and 8, it is fixed to a threading slider 42 that moves up and down in conjunction with the operation of the operating body 65. This guide member 52 is made of a plate material having the shape shown in FIG.
a, and a wide portion 52b is integrally formed below the narrow portion 52a. A slit 52c of a predetermined length is formed in the narrow portion 52a, and the engaging piece 51 of the linking member 50 is inserted into the slit.
By inserting the needle, a threading operation, which will be described later, is executed.

Further, as shown in FIG. 6, below the guide member 52, a wide portion 52b that slightly protrudes to the right (toward the sewing machine operator) from the narrow portion 52a is attached to the back surface of the thread holding member 59 as shown in FIG. Drilled groove 59b
It accepts the information and guides it downward. At this time, the cross section of the groove 59b is formed in a V-shape that expands outward, and the thread holding member 59
is configured to be movable in the swinging direction of the needle bar 30 with respect to the actuating member 71, so as the thread holding member 59 descends, the groove 59b smoothly moves into the wide portion 52.
b. Since the guide member 52 having the wide portion 52b is attached to the threading slider 42 which is disposed in relation to the support frame 29 of the needle bar 30, the concave groove 59b of the thread holding member 59 is connected to the wide portion 52.
b, the thread holding end of the sewing thread 37 is securely inserted into the needle bar 30 (and the eye hole 3 of the sewing needle 34).
3) will be located at the stop position.

(Regarding the Thread Transfer Member) Next, as shown in FIGS. 2 and 5, a guide body 56 having a straight guide surface 56a is vertically moved into the sewing machine frame 21 close to the movement locus of the thread take-up lever 57. The arrangement is fixed. This guide body 56 vertically guides a yarn transfer member 58, which will be described later, and has a known yarn take-up spring body 82 at a predetermined position located on the right side (in FIG. 2) and below.
is fixed.

The thread transfer member 58 is biased by the operating body 65 and guided by the guide body 56 to move down in a timely manner in order to transfer the sewing thread 37 held by the thread take-up lever 57 to the thread take-up spring body 82 of the guide body 56. It is configured like this. That is, as shown in FIGS. 2 and 11, the yarn transfer member 58 is constructed as a base body 58b which is bent into a shape as a whole, and one free end thereof is provided with a locking end 58a having the shape shown in the figure. The sewing thread 37 held by the thread take-up 57 is held in place by the thread take-up lever 57. Further, the other end portion 58c of the base body 58b of the thread transfer member 58 is fixed to the linking member 50 via a screw 75. Therefore, this thread transfer member 58 moves up and down integrally with the up and down movement of the linking member 50 connected to the operating body 65. In this case, the range of linear vertical movement of the locking end 58a of the thread transfer member 58 is from the standby position shown in FIG. 5 to the thread take-up spring body 8 shown in FIG.
It extends to a position below 2.

The thread transfer member 58 is elastically biased upward by the thread holding member 59 and the lifting biasing elastic body 69 of the linking member 50 shown in FIG. The toe 58a is located at a predetermined standby position above the uppermost position of the balance 57, as shown in FIGS. 2 and 5.

As can be seen from FIGS. 2 and 4, the locking end 58a provided at the upper free end of the thread transfer member 58 exceeds the tip of the thread take-up lever 57 in its standby state, and the thread tension lever 57 and the thread tension It is bent into a shape that allows it to enter between the device 54 and the device 54.

(About the thread take-up) As shown in FIG. 5, the thread thread take-up 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 this purpose. The balance 57 is of a link type that 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 publicly known one. 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.

(Connection control means for energizing the threading device) The aforementioned threading device 38 is provided with a connection control means for operating the device with a predetermined time delay by the downward movement of the linking member 50. . That is, the linking member 50 is provided with an engaging piece 51 having a shape as shown in FIGS. It is inserted into the slit 52c and can be moved up and down through the slit. In this case, the length of the slit 52c is such that the length of the slit 52c corresponds to the moving distance of the operating body 65 having the engaging piece 51 inserted therein from the position shown in FIG. 6 to the position shown in FIG. It is set. Then, as the linking member 50 descends with its engaging piece 51 facing the slit 52c, it biases the thread holding member 59 and the thread transporting member 58, but at this stage the threading device 38 is not yet biased. It has not been. However, as shown in FIG. 8, the engaging piece 51 descends through the slit 52c and comes into contact with the lower end of the slit, thereby removing the guide member 52 and the threading slider 4 to which it is attached.
2 is urged downward, thereby starting the threading operation. That is, the threading operation in the threading device 38 is performed by the thread holding member 59 and the thread transporting member 5.
8 is started with a predetermined time delay.

When the threading slider 42 is urged downward together with the guide member 52, the slider 42 is pushed downward in FIGS.
As shown in FIG. 3B, the threading shaft 40 equipped with the threading hook 48 is lowered by a required distance α, and the threading hook 48 is brought to the same position as the eye hole 33 of the sewing needle 34 in the vertical direction. At this point, the guide pin 44 inserted into the slot 43 of the slider 42 comes into contact with the position regulating piece 72 provided at the fixed position, and prevents the threading shaft 40 provided with the threading hook 48 from further lowering. However, since the threading slider 42 is urged downward by the engaging piece 51 via the guide member 52, the threading slider 42 is forced downwardly by the engaging piece 51 through the guide member 52, so that the threading slider 42 is pushed downwardly by the guide pin 44 and the slot 43 as shown in FIG.
The threading shaft 40 is rotated as shown in FIG. 2, and as a result, the threading hook 48 is inserted into the eye hole 33 of the sewing needle 34. In this case, if the slots 43 formed in the threading slider 42 are formed in a zigzag pattern as shown in the figure, the threading shaft 40 will move in its rotating direction as the threading slider 42 descends. is reversed, and the threading hook 48 is pulled out from the eye hole 33 of the sewing needle 34, as shown in FIG. 13d.

That is, the connection control member described above is the connection member 50
The thread holding member 59 is inserted into the eye hole 33 by operating the operation body 65 to insert the thread threading hook 48 into the eye hole 33. The threading hook 48 may
It functions to connect the operating body 65 and the operating body 65.

(Other incidental configurations) As shown in FIGS. 2 and 6, the thread holding member 5
The actuating member 71 having a free end 9 is on standby for threading facing the upper opening 63 of the upper arm 24. During this standby, the thread holding member 5
The posture of the thread holding end 9 has been corrected so that it always faces toward the operator in front of the sewing machine. That is, as shown in FIG. 6, the follower 71c of the actuating member 71
is kept in position by contacting the protruding cam surface 74c of the control cam 74, and in this state, the thread holding member 5
9 is stopped at a standby position, and its thread holding end is directed toward the operator in front of the sewing machine. This facilitates threading work by the operator.

(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. Before sewing with this sewing machine, it is necessary to thread the thread. In the standby state before threading operation, the
5 and 6, the yarn transfer member 58 and the yarn holding member 59 are urged upward by an elastic member 69, and the upper opening 6 at the top of the arm
It protrudes slightly from 3 and stops. As described above, the thread holding member 59 is waiting for threading with its thread holding end facing toward the operator in front of the sewing machine. Further, the locking end 58a of the thread transfer member 58 is connected to the fifth
As shown in the figure, the balance 5 is stopped at the highest position.
It is waiting at a predetermined position above 7.

In this state, the thread spool 61 (thread supply source) stored in the recess 60 provided at the top of the upper arm 24
Pull out the sewing thread 37 that will become the needle thread from the thread guide member 5.
3, the thread tension device 54, and the thread holding hole 57a of the thread take-up lever 57 protruding from the upper opening 63 of the sewing machine head against the elasticity of the tongue piece 87. At this time, the guide wall 81 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. Because of this, the sewing thread 37 is naturally guided into the thread insertion portion 54a of the thread tension device 54 in the thread supply path leading to the guide wall 81 via the thread guide member 53. The sewing thread 37 is further pulled out to the left and is inserted between the thread holding end of the thread holding member 59, that is, the protruding piece 59a and the elastic piece 55, and is elastically held.

After completing this manual work, the operator operates the operating body 65 located on the left side of the upper arm 24 with his or her fingers and pushes it down all at once, thereby threading the thread take-up spring body 82 and threading the sewing needle 34. Eye hole 3
Up to 3 threading tasks can be accomplished automatically. That is, when the operating body 65 is pressed down,
The linking member 50 provided on the operating body 65 is connected to the guide shaft 6
8 and the slit 66 while being guided. Therefore, the thread transfer member 58 and the thread holding member 59 are lowered together with the linking member 50, but the thread holding member 59 is lowered faster than the thread transport member 58 due to the cam mechanism described later. For example, the actuating member 71, which is provided with the thread holding member 59 at one free end and whose other end is pivotally supported by the linking member 50 via the fixed shaft 70, has a follower 71c and a protruding cam provided on the control cam 74. Under the cam action caused by the engagement with the surface 74c, rotation in the clockwise direction from the standby position is started about the shaft 70. Accordingly, the sewing thread 37 held between the thread holding ends 55 and 59a of the thread holding member 59 is pulled out downward through the thread holding hole 57a of the thread take-up lever 57. By utilizing the turning movement caused by the cam action in this way, the descending speed of the thread holding member 59 is reduced by the descending speed of the thread transporting member 58 (that is, the descending speed of the linking member 50 ).

Independently of the action of the thread holding member 59 pulling out the sewing thread 37 downward, the thread transporting member 58 fixed to the linking member 50 descends at a lower speed than the lowering speed of the thread holding member 59. In other words, the thread transfer member 5 that was located above the thread take-up lever 57 during standby
The locking portion 58a of No. 8 is connected to the thread holding hole 57a of the thread take-up 57.
After locking the sewing thread 37 on both sides, the sewing thread 37 is lowered straight along the straight guide surface 56a of the adjacent guide body 56, and is guided to the thread take-up spring body 82, as shown in FIG. . When the pressing force on the operating body 65 is then released, the returning elasticity of the elastic body 69 also causes the thread transfer member 58 fixed to the inserting body 65 and the linking member 50 to rise, so that the sewing thread 37 is straightly aligned with the guide body 56. Information surface 56
It is guided by an indented portion 56b formed in a curved manner at the terminal end of a, and is finally engaged with the thread take-up spring body 82.

Further, as shown in FIG. 6, the follower 71c of the actuating member 71 that has started its rotation descends following the vertical cam surface of the control cam 74, and then moves to the inclined cam surface 71c.
4b, and descends while following this cam surface 74b. As a result, the actuating member 7 of the thread holding member 59
1 rotates under the control of this cam,
The state is as shown in FIG. 8a. When the thread transfer member 58 has rotated to a predetermined angle in this manner, the connection control means for biasing the threading device 38, that is, the engagement piece 51 and the lower end of the slit 52c begin to engage. As a result, the threading slider 42 to which the guide member 52 is fixed descends together with the threading shaft 40, and as the insert body 65 descends, the threading slider 42 moves from the state shown in FIG. 13a to the state shown in FIG. 13b. The threading hook 48 is lowered by the required distance α. Then, the threading hook 48 provided at the lower end of the threading shaft 40 is brought to the same position as the eye hole 33 of the sewing needle 34 in the vertical direction. At this time, the guide pin 44, which is horizontally fixed to the threading shaft 40 and extends through the slot 43 of the threading slider 42, comes into contact with the position regulating piece 72 provided at the fixed position, and the threading Further lowering of the threading shaft 40 with the hook 48 is prevented. However, since the threading slider 42 is urged downward by the engagement piece 51 via the guide member 52, the threading slider 42 is pushed downward by the engagement piece 51 through the guide member 52, so that the threading slider 42 is pushed downward as shown in FIG. The threading shaft 40 is rotated, and as a result, the threading hook 48 is inserted into the eye hole 33 of the sewing needle 34.

In this way, when the threading hook 48 is inserted into the eye hole 33 and is waiting for threading, the ninth
As shown in the figure, a thread holding member 5 holding a sewing thread 37
9 further descends until it reaches a position slightly above the threading hook 48. Next, the follower 7 of the actuating member 71
1c rides on the holding cam surface 74b of the control cam 74, the thread holding member 59 attached to the free end of the operating member 71 descends while being held in that position, and is held at the thread holding end. Sewing thread 37
As shown in the figure, press the threading hook 48 inserted into the eye hole 33 from above. At this time, since the slot 43 in the threading slider 42 has a zigzag pattern as shown in the figure,
Threading slider 42 with guide member 52 attached
As the threading shaft 40 descends, the direction of rotation of the threading shaft 40 is controlled to be reversed. Therefore, at the timing when the sewing thread 37 mentioned above is pressed against the threading hook 48,
If the threading hook 48 is controlled to retreat from the eye hole 33 of the sewing needle 34 as shown in FIG. 13d,
This threading hook 48 hooks the sewing thread 37 when retreating from the eye hole 33, and the thread 37 is pulled out from the eye hole 33 to complete threading.

In this way, the thread holding member 59 holds the sewing thread 37 to the sewing needle 3.
4 and pressed against the threading hook 48, the threading shaft 40 is reversed, and the threading hook 48 is moved from the eye hole 33 with the sewing thread 37 hooked to its tip. retreat and leave,
As a result, the sewing thread 37 is inserted through the eye hole 33 of the sewing needle 34. Therefore, the sewing thread 37, which becomes the upper thread, passes through the thread guide member 53 and the thread insertion portion 5 of the thread tension device 54 described above.
4a, the sewing needle 3 passes through the thread take-up spring body 82 provided on the guide body 56 and the thread holding hole 57a of the thread take-up lever 57.
This means that the needle has been inserted into the eye hole 33 of No. 4, and threading and threading for sewing with the sewing machine are all 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 moved through the slit 66 provided on the left side of the arm and the guide shaft by the return elasticity of the elastic body 69. The actuating member 71 of the thread holding member 59, which is raised to a predetermined standby position while being guided by the connecting member 68 and pivoted to the linking member 50 via the fixed shaft 70, also follows the cam surface of the control cam 74 with its follower 71c. It rotates and rises, and finally stops with its follower 71c in stable contact with the top 74c, as shown in FIG. In addition, the base 5 is attached to the linking member 50.
The thread transfer member 58 fixed via the thread transfer member 8b also returns to its original position and waits for the thread to be threaded onto the next thread take-up spring body 82.

Further, the threading slider 42 also rises under the returning action of the spring 46, and at this time, the threading hook 48 and the threading shaft 40 move to the positions shown in FIGS. 13d to 13a under the engagement of the guide pin 44 and the slot 43. Perform the movements in the reverse order as shown in the diagram to return to the original position.

In this embodiment, the sewing thread 37 is inserted in advance into the thread holding hole 57a of the thread take-up 57 before the thread threading operation. The hook may automatically catch the sewing thread 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.

Effects of the Embodiment According to the sewing machine capable of automatically threading the thread according to the embodiment of the present invention, the thread spool can be set by simply pressing down the operation body 65 provided on the outside of the upper arm 24 of the sewing machine so as to be able to move up and down. While hanging the sewing thread 37 supplied from the thread take-up spring body 82 from the thread take-up spring body 82,
Transfer the sewing thread 37 to the eye hole 33 of the sewing needle 34,
Further, the threading hook 48 inserted into the eye hole 33 and waiting catches the sewing thread 37 and retreats, thereby facilitating threading and threading in a predetermined order, which conventionally required troublesome effort. It is possible.

In addition, the linking member 50 that links the thread transfer member 58 and the thread holding member 59 is configured to start operating the two members at different times, thereby preventing sudden withdrawal of the sewing thread from the thread supply source. , therefore, the eye hole 3 of the sewing needle 34 passes through the thread take-up spring body 82.
Transfer of the suture thread 37 up to 3 times can be reliably achieved. Moreover, the thread transfer member 58, the thread holding member 59, and the linking member 5 that operates these members in conjunction with each other.
0 has a simple configuration, making it easy to manufacture and reducing manufacturing costs.

Effects of the Invention As explained above, according to the automatic threading device for a sewing machine according to the present invention, threading work of a sewing machine, which conventionally required multiple operations, can be performed from a thread supply source by a single moving operation of an operating body. The drawn-out sewing thread can be threaded onto the thread take-up spring body, and the thread can be transported to a position near the eye of the sewing needle where it can be reliably captured by the threading hook, thereby facilitating threading and threading operations. can be achieved. In addition, the structure is simple because the thread transfer member that transfers and threads the sewing thread to the thread take-up spring body is fixed on the linking member that links the operating member that moves the thread holding member and the operating body. This makes it easy to place the sewing machine in a narrow space within the frame of the sewing machine.

[Brief explanation of drawings]

The drawings show a preferred embodiment of a sewing machine incorporating an automatic threading mechanism according to the present invention.
The figure is a front view showing the overall external configuration of a sewing machine according to a preferred embodiment, FIG. 2 is a partially cutaway front view showing the main parts of the sewing machine shown in FIG. 1, and FIG. FIG. 4 is a partially cutaway plan view showing the main parts of the sewing machine shown in FIG. 3, FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 2, and FIG. 6-6 line cross-sectional views, FIGS. 7, 8a, 8b, and 9, the thread holding member, thread transfer member, and threading device are moved to a predetermined position via the linking member by pressing down the operating body. FIG. 8b is a view taken in the direction of the Z arrow in FIG. 8a, and FIG. 10 is a diagram showing the state in which the thread holding member is in the vicinity of the eye hole of the sewing needle. 11 is an exploded configuration diagram of the main part of the present invention, and FIG. 12 is a thread holder. Explanatory diagrams showing a state in which a member is guided by a guide member, Figures 13a to 13d
The figure shows that after the threading hook is inserted into the eye of the sewing needle,
It is an explanatory view showing a state over time until it is retreated and extracted from the eye hole. 21... Sewing machine frame, 30... Needle bar, 33...
Eye hole, 34... Sewing needle, 37... Sewing thread, 38... Threading device, 48... Threading hook, 50... Linking member, 54... Thread tension device, 56... Guide body, 5
7... Balance, 57a... Thread holding hole, 58... Thread transfer member, 58a... Locking end, 59... Thread holding member, 65... Operating body, 71... Operating member, 82...
...Thread take-up spring body.

Claims (1)

[Scope of 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 eyelet 33 through which a sewing thread 37 is inserted, a thread tension device 54 from a thread supply source 61,
The sewing needle 34 passes through the thread take-up spring body 82 and the thread take-up lever 57.
threading hook 48 that is operable to capture the thread 37 that has been fed up to the eye hole 33 and thread it through the eye hole 33;
In the sewing machine equipped with a threading device 38 having a thread holding member 59 that releasably holds the sewing thread 37.
and supports the thread holding member 59, and supports the thread holding member 59.
an operating member 71 that can be operated to move the sewing machine from a predetermined position to at least the eye hole 33 of the sewing needle 34; a single operating member 65 disposed on the sewing machine frame 21 so as to be able to move vertically; It has a linking member 50 that links the operation with the operation of the operating member 71, and a locking end 58a for locking the sewing thread 37 held by the thread take-up 57. The locking end 58a is connected to the thread take-up spring body 8.
fixed on the linking member 50 in order to move up to 2.