JPS6257590A - Automatic yarn passing type sewing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This 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, and more particularly, a thread is supplied from a thread supply source to an eye of a sewing needle via a thread tension device, a thread take-up spring body, and a thread thread take-up. In a sewing machine equipped with a threading device that captures the thread that has been removed by a threading hook and inserts it into the eyelet, the sewing thread pulled out from the thread supply source can be moved to the thread take-up spring body by simply pressing the operating body. The machine automatically threads the sewing thread, and also transports the sewing thread to the eye of the sewing needle, where it is captured by the threading hook waiting to be inserted into the eye and threaded. It is related to sewing machines.

The preparatory work for sewing processed fabric using a conventional sewing machine is as follows:
It is necessary to hook the needle thread pulled out from the thread spool to various members such as the thread tension plate, thread take-up spring body, thread take-up lever, etc. in a predetermined order and route, and then insert the sewing thread into the eye of the sewing needle. be. 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, simply performs the task of 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 plate, 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 this series of threading is done in the wrong order, the sewing work will not be able to be completed 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. Ru.

One example of a device that automatically performs threading and threading in a sewing machine is the invention "Automatic threading device for a sewing machine" proposed by the present applicant.

It is 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 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 operational reliability is also poor.

Purpose of the Invention The present invention has been proposed in view of the above-mentioned disadvantages inherent in sewing machines equipped with a threading device according to the prior art, and has been proposed to suitably solve these problems. The sewing thread is pulled out and threaded onto the thread take-up spring body, and the sewing thread is transported to the front of the threading hook inserted into the eye of the sewing needle.
A threading operation in which the sewing thread is caught by the hook and pulled out from the eye hole can be easily accomplished by a single movement operation of the operating body, and at this time, the sewing thread is prevented from being pulled out suddenly from the thread supply source. This allows for smooth suture transfer.

Another object of the present invention is to provide a sewing machine capable of automatic threading with a simplified mechanism.

Means for Solving the Problems In order to suitably solve the above-mentioned problems, the present invention is provided by attaching the needle bar 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. a thread holding member that releasably holds sewing thread;
an operating member operable to support the thread holding member and move the thread holding member from a predetermined position to at least the eye of the sewing needle; and a single operating member disposed on the sewing machine frame so as to be movable up and down. , a linking member that links the operation of the operating body with the operation of the operating member, and a locking end for locking the suture held in the thread take-up; The present invention is characterized in that it is configured to include a thread transfer member fixedly provided on the linking member for moving the toe to the thread take-up spring body.

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 in relation to the linking member connected to the operating body starts to descend,
The sewing thread held by the thread holding member supported by the actuating member is pulled out downward.

In addition, in synchronization with the lowering of the actuating member and with a delay in speed, the thread feeding member fixed to the linking member started lowering and was held by the thread take-up. Alternatively, the sewing thread to be held is guided to the vicinity of the thread take-up spring body while being hooked to the locking end. Further, the thread holding member holding the sewing thread moves the sewing thread to the eye of the sewing needle by descending, and engages the thread with a threading hook that is inserted into the eye of the sewing needle and is waiting.

The threading hook then flips in time to capture the suture and withdraw the hook from the eye of the sewing needle, thereby completing threading 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. 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. It basically consists of a lower arm 23 provided with a processing surface, an upper arm 24 extending in parallel above this lower arm 23 and having a sewing machine head at its tip, and a pillar 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 arranged at an appropriate position.
A block-shaped needle bar stand 27 is vertically fixed to this basic frame 26, and a support frame 29 is attached to this needle bar stand 27 via a support shaft 28, and is horizontally rotatable at its protrusions 29a, 29b. It is supported by an insertion shaft. A needle bar 30 is inserted through the support frame 29 so as to be able to reciprocate up and down, and this needle bar 30 is connected to a needle bar crank 31 via a needle bar holder (not shown).
It is designed to be reciprocated up and down 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, a connecting frame 36 shown in FIGS. 4 and 5 is pivotally attached to the support frame 29, and by reciprocating the connecting frame 36 in the horizontal direction by a pulse motor (not shown), the needle bar 30 is moved in a zigzag manner. It is designed to provide the lateral rocking motion necessary for sewing.

(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 can be seen from FIGS. 2, 4, and 6, along the vertical sides of the support frame 29,
A threading guide plate 39 formed in an elongated U-shape is provided,
It is pivotally supported by the support frame 29 at both upper and lower end edges so as to be able to pivot around the needle bar 30 by a required angle. This guide plate 39 has a vertical slit 39 with a predetermined width.
a 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 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), two bolts 42a inserted into the slit 39a,
42a, and is movable 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, slots 43 are transparently provided in the slider 42 in a predetermined pattern.
A guide pin 44 horizontally fixed to the threading shaft 40 is inserted therein, and a compression spring 45 shown in FIG.
0 is always elastically biased downward. Also, between the threading slider 42 and the protrusion 39a of the guide plate 39,
Spring means 46 consisting of a tension spring shown in FIGS. 6 and 7
is engaged, and the slider 42 is constantly lifted and biased upward by its elasticity. 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.
A threading hook 48 curved from above and protectors 49 and 49 each consisting of two tongues extending horizontally sandwiching the hook 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, the surface protector 49 is 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 5
4, a guide wall 81, a guide body 56, a thread take-up 57, a thread diameter feeding member 58 and a thread holding member 59, which will be described in detail later, are arranged in this order in the left direction. As shown in the plan view 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.

Also, the thread guide member 5 guides the sewing thread 37 to the thread tension device 54.
3 to the locking end 5 of the yarn diameter feeding member 58 waiting in a predetermined position.
The thread insertion part 54a of the thread tension device 54 is set to be oriented in the arrangement direction toward 8a (FIG. 4),
A guide wall 81 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 member 54a, respectively.

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 diameter feeding member 58 and thread holding member 59 to protrude slightly. Further, as shown in FIGS. 6 and 9, the lower surface of the upper arm 24 has a sewing thread 37. A lower opening 64 is provided to allow passage of a portion of the thread holding member 59 and thread feeding member 58. Note that the balance 57 is
Since the upper arm 24 reciprocates up and down in an arc shape, the front part of the arm 24 does not have a slit for passing the thread take-up, as seen in conventional sewing machines, as shown in FIG. It 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. 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 12, a thread holding member 59 that releasably holds the sewing thread 37 is disposed in the upper arm 24, and the operating body 65 By this 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 on the left side surface of the upper arm 24 shown in FIG. 2, 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, a holding frame 67 having a shape shown in FIG. 6 is arranged and fixed inside the upper arm 24.
Ends 67a, 6 that protrude horizontally from 7 and are vertically opposed to each other.
A guide shaft 68 is vertically inserted and fixed between the guide shafts 7b, and the linking member 50 is inserted through the guide shaft 68 so as to be movable up and down (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 actuating member 71, which will be described later, is pivotally supported on the linking member 50 via a fixed shaft 70, and a tongue piece 71 formed on the actuating member 71
As shown in FIG. 6, a tension spring 69 is tensioned between the upper arm 24 and the inner top surface of the upper arm 24, thereby urging the linking member 50 and the operating body 65 in the lifting direction.

As clearly shown in FIGS. 6 and 11, the interlocking member 5
An actuating member 71 having the shape shown in the figure is pivotally attached to a portion located rearward of the needle bar 30 in FIG. 0 via a fixed shaft 70. 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 connected to the fixed shaft 7
0 within a required angle range, and allows the thread holding member 59 (described later) to be rotated within a plane including the needle bar 3o (Figs. 5 to 5).
(Fig. 9).

One free end of the actuating member 71 is arranged as shown in FIG.
A thread holding member 59 (described later with reference to FIGS. 10 and 12), which is bent into a U-shape and holds the sewing thread 37 in a releasable manner, is rotatable via a # pin 73. It is set in. Further, at the opposite end of the actuating member 71, as shown in FIG.
Crotch-shaped followers 7lb and 71c 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 disposed within 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. Also, 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 thread holding member 59 is moved up and down around the eye hole 33. A linear holding cam surface 74b is also formed which holds the rotational posture of the actuating member 71 constant via the followers 7] and c while the actuating member 71 is located within a predetermined range of directions.

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 5o inserted through the guide shaft 68 is lowered by a predetermined distance together with the operating member 71 against the elasticity of the elastic member 69 by pushing down the operating member 65 connected thereto outside the sewing machine frame. As shown in FIG. 7, the follower 71b of the actuating member 71 comes into contact with and follows the protruding cam surface 74c of the control cam 74, so that the actuating member 71 moves one turn 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,
It is provided with thread holding ends that releasably hold the sewing thread 37 at appropriate locations, and is movable relative to the operating member 71 in the swinging direction of the needle bar 3o. That is, the thread holding end portion that releasably holds the sewing thread 37 has a protruding piece 59a formed integrally with the thread holding member 59, and is fixed to the thread holding member 59 and protrudes slightly forward of the protruding piece 59a. It is composed of a metal elastic piece 55. The thread holding end portion consisting of the projecting piece 59a and the metal elastic piece 55 is inserted into the eye hole 33 of the sewing needle 34 while holding the sewing thread 37 as the operating member 71 rotates, as shown in FIG. The sewing thread 37 is brought to the position of the threading hook 48.

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.

Note that in the zigzag sewing machine, the needle bar 3o 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 pressure operation of the operating body 65, the thread holding end holding the sewing thread 37 does not necessarily reach the stopping position of the needle bar 30 and the sewing needle 34. Then, attach the thread holding end holding the sewing thread 37 to the sewing needle 34.
As shown in FIGS. 11 and 8, the guide member 52, which is engageable with the thread holding member 59, is operated in conjunction with the operation of the operating body 65 for the purpose of guiding the thread to a position close to the eye hole 33 of the thread holding member 59. It is fixed to a threading slider 42 that moves up and down. This guide member 52 is made of a plate material having the shape shown in FIG.
The upper part thereof is formed as a narrow part 52a, and a wide part 52b is integrally formed below the narrow part 52a. A slit 52c of a predetermined length is formed in the narrow portion 52a, and by inserting the engagement piece 51 of the linking member 50 into the slit, a threading operation to be described later is performed.

Further, as shown in FIG. 6, a wide portion 52b that slightly protrudes to the right (towards the sewing machine operator) from the one narrow portion 52a below the guide member 52 is attached to the back surface of the thread holding member 59 as shown in FIG. The receptacle is inserted into the bored groove 59b and guided 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 movable in the direction of the swinging force of the needle bar 30 with respect to the operating member 71. Therefore, as the thread holding member 59 descends, the groove 59b is smoothly introduced into the wide portion 52b. The guide member 52 including the wide portion 52b is connected to the needle bar 3.
The threading slider 42 is arranged in relation to the support frame 29 of 0.
Since it is attached to the groove 59b of the thread holding member 59,
is inserted into the wide part 52b, so that the thread holding end of the sewing thread 37 is fixed.

This ensures that the needle bar 30 (and the eyelet 33 of the sewing needle 34) is located at the stopping position.

(About the yarn transfer member) Next, as shown in FIGS. 2 and 5, the straight guide surface 5
A guide body 56 having a guide member 6a is disposed and fixed vertically within the sewing machine frame 21 close to the movement trajectory of the thread take-up lever 57.

This guide body 56 is for vertically guiding a thread transfer member 58, which will be described later.

A known thread take-up spring body 82 is fixed at a predetermined position located on the right side (in FIG. 2) and below.

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 configured as a base body 58b that is bent into a U-shape as a whole,
A locking end 58a having the shape shown in the figure is provided at one free end thereof, and the sewing thread 37 held by the thread take-up 57 is locked thereby. Also, the base body 58b in the thread transfer member 58
The other end 58c is fixed to the linking member 50 via a screw 75. Therefore, this thread transfer member 58
It moves up and down integrally with the up and down movements of the linking member 50 connected to the linking member 50. In this case, the range of linear vertical movement of the locking end 58a of the thread transfer member 58 is
It extends from the standby position shown in the figure to a position below the thread take-up spring body 82 shown in FIG.

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

A locking end 58 provided at the upper free end of the thread transfer member 58
As can be seen from FIGS. 2 and 4, a crosses the tip of the balance 57 in its standby state, and
7 and the thread tension device 54.

(About the thread take-up) As shown in FIG. 5, the 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 prevention. This thread take-up 57 is connected to a link (not shown) that is pivotally supported on a shaft 88 on the base frame 26 in the sewing machine frame 21, and also connects to the needle bar crank 31.
This is a well-known link-type device that is connected to a motor to provide a predetermined reciprocating motion. 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 above-mentioned threading device 3 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 engagement piece 51 inserted therein from the position shown in FIG. 6 to the position shown in FIG. It is set. Then, while the linking member 50 is descending with its engaging piece 51 facing the slit 52c, it urges the thread holding member 59 and the thread transporting member 58.
At this stage, the threading device 38 is not yet energized.

However, as shown in FIG.
2c and abuts against the lower end of the slit, the guide member 52 and the threading slider 42 to which it is attached are urged downward, thereby starting the threading operation. That is, the threading operation in the threading device 38 is started with a predetermined time delay with respect to the operations of the thread holding member 59 and the thread transporting member 58.

When the threading slider 42 is urged downward together with the guide member 52 in this way, the slider moves as shown in FIGS. 13(a) and 13(b), as will be described later regarding the operation. Threader 4i [114
0, the threading hook 48 descends by a required distance α.
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 the threading shaft 44 equipped with the threading hook 48
Prevent further fall of 0. However, threading slider 4
2 is urged downward by the engaging piece 51 via the guide member 52, so that the thread can be threaded under the cooperation of the guide pin 44 and the slot 43 as shown in FIG. 13(Q). The shaft 4o is rotated, 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, as the threading slider 42 descends, the threading shaft 40 will move in the direction of rotation. is reversed, and the threading hook 48 is pulled out from the eye hole 33 of the sewing needle 34, as shown in FIG. 13(d).

That is, the connection control member is made up of an engaging piece 51 provided on the linking member 50 and a slit 52c formed in the guide member 52, and the threading hook 48 is inserted into the eye hole 33 by operating the operating body 65. With.

It functions to connect the threading hook 48 and the operating body 65 in all or part of the operating area, which is a predetermined operating position until the thread holding member 59 reaches the eye hole 33. .

(Other Ancillary Structures) As shown in FIGS. 2 and 6, the actuating member 71, which has the thread holding member 59 at its free end, faces the upper opening 63 of the upper arm 24 and waits for threading. However, during this standby period, the posture of the thread holding end of the thread holding member 59 is corrected so that it is always oriented 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 held in position by contacting the protruding cam surface 74c of the control cam 74, and in this state, the thread holding member 59 is stopped at the standby position. The thread holding end is directed toward the operator in front of the sewing machine. This facilitates threading 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. 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 diameter feeding member 58 and the thread holding member 59 are urged upward by the elastic member 69, It slightly protrudes from the upper opening 63 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, as shown in FIG. 5, the locking end 58a of the thread diameter feeding member 58 is waiting at a predetermined position above the thread take-up 57 which is stopped at the uppermost position.

In this state, the needle thread 37 is pulled out from the thread spool 61 (thread supply source) stored in the recess 60 provided at the top of the upper arm 24, and is passed through the thread guide member 53 and the thread tension device 54. , the tongue piece 87 is inserted into 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 locking portion 58 of the thread tension device 54 and the thread diameter feeding member 58
As described above, the guide wall 81 interposed between the thread guide member 53 and the guide wall 81 is formed to extend in the arrangement direction from the thread guide member 53 toward the locking portion 58a in the standby position. In the thread supply path leading to the wall 81, the sewing thread 37 is naturally guided into the thread insertion portion 54a of the thread tension device 54. 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. Threading work up to the eye hole 33 can be automatically accomplished. That is, when the operating body 65 is pushed down, the linking member 50 provided on the operating body 65 starts to descend while being guided by the guide shaft 68 and the slit 66. Therefore, the thread diameter feeding member 58 and the thread holding member 59 are lowered together with the linking member 50, but the thread holding member 59 is lower than the thread diameter feeding member 58 due to the cam mechanism described later.
descend faster than For example, the thread holding member 59 is provided at one free end, and the other end is connected to the linking member 59 via the fixed shaft 70.
The actuating member 71, which is pivoted at 0, rotates clockwise from the standby position about the shaft 70 under the cam action caused by the engagement of its follower 71c with a protruding cam surface 74c provided on the control cam 74. start the movement. Accordingly, the sewing thread 37 held between the thread holding ends (55, 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 feeding member 58 (that is, the descending speed of the linking member 50), as shown in FIGS. 7 and 8. speed).

The thread diameter feeding member 58 fixed to the linking member 5o is independent of the action of the thread holding member 59 that largely pulls out the sewing thread 37 downward.
is lowered at a lower speed than the lowering speed of the thread holding member 59. That is, the locking portion 58a of the yarn diameter feeding member '58, which was located above the thread take-up lever 57 during standby,
After the sewing thread 37 is locked on both sides of the thread holding hole 57a, it descends straight along the straight guide surface 56a of the adjacent guide body 56 and reaches the thread take-up spring body 82, as shown in FIG. Guide the sewing thread 37. After that, when the pressing force on the operating body 65 is released, the returning elasticity of the elastic body 69 also causes the thread transfer member 58 fixed to the operating body 65 and the linking member 50 to rise.
The indented part 5 is curved at the end of the straight guide surface 56a of 6.
6b, 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, which has started its rotation, descends following the vertical cam surface of the control cam 74, and then rides on the inclined cam surface 74b. It descends while following the second cam surface 74b. As a result, the actuating member 71 of the thread holding member 59 rotates while being controlled by this cam, and is in the state shown in FIG. 8(a). When the thread transfer member 58 has rotated to a predetermined angle in this way, the connection control means that biases the threading device 38 described above, that is, the engagement piece 51 and the slit 52c.
The lower end of starts engaging. As a result, the threading slider 42 to which the guide member 52 is fixed descends together with the threading shaft 4o, and as the operating body 65 descends, the state shifts from the state shown in FIG. 13(a) to the state shown in FIG. 13(b). During this time, the threading hook 48 is lowered by the required distance α. Then, attach the threading hook 48 provided at the lower end of the threading shaft 40 to the sewing needle 34.
It is made to arrive at the same position in the vertical direction as the eye hole 33 of.

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, the threading slider 42
Since it is urged downward by the engagement piece 51 via the guide member 52, the threading shaft 4 is moved under the cooperation of the guide pin 44 and the slot 43 as shown in FIG. 13(c).
As a result, the threading hook 48 is inserted into the eye hole 33 of the sewing needle 34.

When the threading hook 48 is inserted into the eye hole 33 and is waiting for threading, as shown in FIG.
The thread holding member 59 holding the sewing thread 37 further descends and reaches a position slightly above the threading hook 48. Next, when the follower 71c of the operating member 71 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. The sewing thread 37 held at the thread holding end is pressed from above onto the threading hook 48 inserted through the eye hole 33, as shown in FIG. At this time, the pattern of the slots 43 in the threading slider 42 is a zigzag pattern as shown in the figure.

As the threading slider 42 to which the guide member 52 is attached descends, the direction of rotation of the threading shaft 40 is controlled to be reversed. Therefore, if the threading hook 48 is controlled to retreat from the eye hole 33 of the sewing needle 34 at the timing when the sewing thread 37 is pressed against the threading hook 48 as shown in FIG. 48 hooks the sewing thread 37 when retreating from the eye hole 33, and the sewing thread 37
threading is accomplished by pulling out the thread completely.

In this manner, when 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 threading shaft 4o is reversed, so that the threading hook 48 is moved to its tip. With sewing thread 37 hooked, open eye hole 3.
3, and the sewing thread 37 is thereby inserted into the eye hole 33 of the sewing needle 34. Therefore, the sewing thread 37 which becomes the upper thread is
The thread guide member 53 and the thread insertion portion 5 of the thread tension device 54 described above
4a, the eye 33 of the sewing needle 34 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 57.
This means that all the threading and threading operations for machine sewing are 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. While rotating, it finally stops with the follower 71c in stable contact with the top 74c, as shown in FIG. Further, the thread feeding member 58 fixed to the linking member 5o via the base body 58b 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 are engaged with the guide pin 44 and the slot 43 as shown in FIG. 13(d). - Perform the previous operation in the reverse order as shown in Fig. 13(a) 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 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.

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 easily threaded by manually pushing 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. The sewing thread 37 supplied from the thread take-up spring body 8
2 and thread the sewing thread 37 through 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 moves back, thereby threading and threading in a predetermined order, which conventionally required troublesome work. It is something that can be easily passed through.

In addition, since the linking member 50 that operates the thread diameter feeding member 58 and the thread holding member 59 in conjunction with each other is designed to start operating at different times, sudden withdrawal of sewing thread from the thread supply source is prevented. Therefore, the sewing thread 37 can be reliably transferred to the eye hole 33 of the sewing needle 34 via the thread take-up spring body 82. Moreover, the thread diameter feeding member 58 and the thread holding member 59
and a linking member 50 that operates these two members in a linked manner.
Since it has a simple configuration, it is easy to manufacture and can reduce manufacturing costs.

As described in detail, the automatic thread threading of a sewing machine according to the present invention can thread the thread by a single moving operation of the operating body in the threading operation of the sewing machine, which conventionally required multiple operations. The sewing thread pulled out from the supply source 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 caught by the threading hook, thereby facilitating the threading and threading operations. can be easily achieved. In addition, the construction is simple because the thread feeding 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, 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 of 5-511fA in FIG. 2, and FIG. 6 is a 6-511fA cross-sectional view in FIG.
- 6-line cross-sectional view, Figures 7, 8(a) and 8(b)
) and FIG. 9 are schematic operation diagrams illustrating over time the state in which the thread holding member, thread diameter feeding member, and threading device operate with a predetermined time difference via a linking member when the operating body is pressed down, FIG. 8(b) is a view taken from the direction of the Z arrow in FIG. 8(a), and FIG. 10 shows the thread holding member reaching a position near the eye of the sewing needle, inserting it into the eye, and waiting to be captured. Fig. 11 is an exploded configuration diagram of the main parts of the present invention, and Fig. 12 is an explanation showing a state in which the thread holding member is guided by the guide member. Figures 13(a) to 13(d) show the state in which the threading hook is inserted into the eye of the sewing needle over time until it is retreated and pulled out from the eye. It is an explanatory diagram. 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 57...
- Take-up lever 57a - Thread holding hole 58 - Thread diameter feeding member 58a - Locking end 59 - Thread holding member 65 - Operating body 71 - Operating member 82 - Thread take-up spring body F
IG,5 FIG,6 (a) FIG,8':)':j! :l! =la! :) Ri j'/
FIG, 9 FIG, 10

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 eyelet (33) through which a sewing thread (37) is inserted, and a thread supply source. (61) to the thread tension device (5
4), the sewing thread (37) is supplied to the eye hole (33) of the sewing needle (34) via the thread take-up spring body (82) and the thread take-up (57).
) and a threading device (38) having a threading hook (48) operable to capture and pass the sewing thread (37) through the eye hole (33), a thread holder for releasably holding the sewing thread (37) Parts (59)
and supporting the thread holding member (59), and supporting the thread holding member (59).
from the specified position to at least the eye hole (33) of the sewing needle (34).
an actuating member (71) operable to move up to
A single operating body (65) arranged on the sewing machine frame (21) so as to be able to move up and down, and a linking member (50) that links the operation of the operating body (65) 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) being connected to the operation of the operating body (65). The thread take-up spring body (
a thread transfer member (58) fixedly mounted on said linkage member (50) for movement up to (82). 2. The thread transfer member (58) is connected to the linking member (50)
A guide body (56) is bent together with the guide body (56), and its locking end (58a) is provided close to the movement locus of the balance (57).
2. A sewing machine capable of automatic threading according to claim 1, characterized in that the sewing machine is guided in the vertical direction by a threader.