JPS58358B2 - Sewing machine tacking device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sewing machine tacking device for preventing thread tangling in sewn products, and its object is to operate a solenoid by operating one manual operation member. The purpose of this invention is to reverse the feed and reduce the amplitude of the needle bar to zero so that tacking stitches can be performed, and another purpose is to allow a forward edge to be created when making buttonholes.

The present invention will be described in detail with reference to the drawings below. Reference numeral 1 denotes one of the selection cams rotatably mounted on a mechanism base (not shown) fixed to the sewing machine arm. , the cam is driven intermittently.

3 is an amplitude limiting cam fitted to a shaft 4 fixed to the mechanism base;
The cam is connected to a gear 5, a bevel gear 6, a main shaft (not shown) rotatably supported on the arm via a bevel gear 7 meshing with the bevel gear and fitted on the shaft 4, and a clutch ring 8. ).

9 is a follower fitted to a shaft 10 implanted in the mechanism stand;
A claw portion 9a that engages with the selection cam 1 is formed at its upper end, and the left end of a feed adjustment rod 11 is pivotally attached to its lower end.

Reference numeral 12 denotes a spring that biases the follower 9 clockwise, that is, so as to press into engagement with the selection cam 1.

Reference numeral 13 denotes an amplitude adjusting arm fitted onto a shaft 14 implanted in the mechanism base, and a claw portion 13 that engages with the amplitude limiting cam 3 is provided at the right end of the arm.
A is formed, and its left end is connected to the needle bar so as to adjust the needle bar amplitude.

Reference numeral 15 denotes a substantially right-angled feed converting arm that is fitted onto a shaft 16 fixed to the mechanism table. A pin 15a is implanted at one end of the arm, and a feed converting rod 17 is pivotally attached to the other end. ,
Further, a pin 15b is implanted near the other end.

Reference numeral 18 denotes a spring that urges the feed converting arm 15 to rotate clockwise.

11a is a U-shaped notch formed on the right side of the feed adjustment rod 11, and the pin 15 of the feed conversion arm 15 is inserted into the notch.
a is loosely fitted, and 19 is the feed adjustment rod 1.
This is a spring that biases 1 to pull it upward.

Therefore, the bottom surface of the notch 11a of the feed adjustment rod 11 is always in pressure contact with the pin 15a of the feed conversion arm 15.

20 is a rod arm fitted to the shaft 16, one end of which engages with a pin 11b implanted in the feed adjustment rod 11, a link 21 is pivotally attached to the lower end of the rod arm 20; with a spring that urges it to rotate counterclockwise.
Therefore, the rod arm 20 is connected to the pin 11b of the feed adjustment rod 11.
It is designed to press into engagement with the

23 is a solenoid mounted on the mechanism base, 24 is a plunger of the solenoid, 25 is a locking piece pivotally attached to the upper end thereof, and the tip thereof has a claw portion that can be locked to the pin 11c of the feed adjustment rod 11. 25a, and the feed conversion arm 1 is located approximately in the center thereof.
A notch 25b that can be engaged with the pin 15b of No. 5 is formed in each case, and a link 21 is formed slightly below the center of the notch 25b.
The pin 25 is inserted into the long hole 21a drilled at the left end of the pin 25.
c is planted.

Reference numeral 26 denotes a spring that urges the locking piece 25 to rotate counterclockwise, and this spring is set to be weaker than the spring pressure of the spring 22 of the rod arm 20.

27 is a lower shaft rotatably supported on a bed part (not shown) in parallel with the main shaft, 28 is a feed reversing mechanism (details thereof are not shown) attached to said one shaft, and 29 is a shaft mounted on the bed part. It is a reversing arm rotatably fitted to a fixed shaft 30, one end of which is pivoted to the lower end of the feed conversion rod 17, and a pin 29a implanted in the other end. It is formed in the feed reversing mechanism 28 section and fitted into an annular groove 28a.

31 is an operating arm fitted into a shaft 32 fixed to the mechanism base;
33 is a torsion spring that urges the actuating arm 31 to rotate clockwise; therefore, the pin 31a is pressed into engagement with the amplitude limiting cam 3. It's like getting it.

34 is a link pivotally connected to the upper end of the plunger 24 of the solenoid 23 in parallel with the locking piece 25; 35 is a connecting arm fitted to the shaft 16; The link 34 is engaged with the other end 31b.
A spring 36 biases the connecting arm 35 to rotate clockwise, so that the plunger 24 is pulled upward via the link 34.

The amplitude limiting cam 3 is formed with an external cam 3a, a side cam 3b, and a protrusion 3c, and the clutch ring 8 has a recess 8a that can engage with the protrusion 3c of the amplitude limiting cam 3, and a protrusion 7a of the bevel gear 7. Engaging recesses 8b are respectively formed.

By the way, FIG. 1 shows the external appearance of a sewing machine incorporating the device according to the present invention, and shows the selection buttons 37, 38, 39.
．． ...Furthermore, by turning on the R button 52, which is an example of a manual operation member, the amplitude, feed amount, etc. suitable for various pattern stitches are set. When the button 52 is turned on, the solenoid 23
It is energized to reduce the amplitude to zero and reverse the feed.The details will be explained next.

When the solenoid 23 is energized in the state shown in FIGS. 2 and 4, the plunger 24 moves downward against the spring 18 to rotate the feed converting arm 15 counterclockwise.
Accordingly, the feed converting rod 17 also moves downward, and the reversing arm 29 rotates clockwise to change the feed phase by about 180 degrees, thereby making the feed reverse.

At the same time, when the solenoid 23 is energized in FIGS. 2, 3, and 5, the plunger 24 moves against the spring 36 and
The pin 31a of the actuating arm 31 moves downward as if rotating in the counterclockwise direction.
It becomes like engaging with.

In FIG. 3, 53 is a return spring that presses the amplitude limiting cam 3 toward the clutch ring 8, and 54 is a clutch spring that presses the clutch ring 8 toward the amplitude limiting cam 3. The spring pressure of this spring is weaker than that of the return spring 53. It is set.

In the state shown in FIG. 3, the amplitude limiting cam 3 engages with the clutch ring 8 and rotates in conjunction with the main shaft.

When the pin 31a of the actuating arm 31 reaches point a of the side cam 3b and the claw portion 13a of the amplitude adjusting arm 13 reaches the position facing the lowest part of the external cam 3a, the amplitude limiting cam 3 moves the amplitude adjusting arm 13. The outer cam 3a and the amplitude adjustment arm 13 move to the side.
When the amplitude limiting cam 3 further rotates and the pin 31a of the operating arm 31 reaches the point b of the side cam 3b, the amplitude limiting cam 3 further engages with the claw portion 13a of the amplitude adjusting arm. 13
Move to the side and finally the clutch ring 8 and amplitude limiting cam 3
The claw portion 13a of the amplitude adjusting arm 13 comes to engage with the highest part of the external cam 3a, and in this state it remains stationary, and the amplitude of the needle bar is zero.

In other words, it is in a state of straight sewing.

Due to the above action, when the R button 52 is turned ON, the feed is reversed and the amplitude is zero, but when the R button 52 is turned OFF, the solenoid 23 is deenergized and the feed conversion rod 17 is The clutch ring 8 is moved upward to return the feed phase to its original state, and at the same time, the engagement between the pin 31a of the operating arm 31 and the side cam 3b is released, and the clutch ring 8 is moved toward the amplitude limiting cam 3 by the clutch spring 54. Then, the clutch ring 8 and the amplitude limiting cam 3 engage again, the amplitude limiting cam 3 rotates, and when the pin 31a of the operating arm 31 reaches the lowest part of the external cam 3a, the amplitude limiting cam 3 is moved by the return spring 53. It moves to the clutch ring 8 side and rotates with the swing width adjusting arm 13 and the claw portion 13a disengaged.

FIG. 6 shows the state of the tacking stitch when sewing buttonholes. When the selection button 42 in FIG.
is intermittently driven so that the claw portion 9a of the follower 9 engages with the valley of the cam, and accordingly, the feed adjustment rod 11 moves to the left, and the locking piece 25 engages with the pin 11c. It becomes like doing.

In this state, the engagement between the notch 25b of the locking piece 25 and the pin 15b of the feed conversion arm 15 has already been released, so that the pin 15a of the feed conversion arm 15 is connected to the feed adjustment rod 1.
It rotates slightly clockwise by the spring 18 until it comes into contact with the right end surface of the notch 11a.

When the R button 52 is turned on in this state, the locking piece 25 is pushed down by the plunger 24 as described above, and the feed adjustment rod 11 and the feed conversion arm 15 are accordingly pushed down.
The feed converting rod 17 is pushed upward via the inverting arm 29, and the feed phase is reversed to the forward line via the reversing arm 29. In this state, the buttonhole can be sewn.

According to the present invention, when one manual operation member 52 is operated, the solenoid 23 is turned on, and in conjunction with the solenoid, the feed reversing mechanism 28 is activated to reverse the feed, and the operating arm 31 is the side cam 3 of the amplitude limiting cam 3
b, and the amplitude limiting cam is engaged with the protrusion 3 of the amplitude limiting cam.
c and the concave portion 8a of the clutch ring 8 are disengaged from each other in the axial direction, and the claw portion 13a of the amplitude adjusting arm 13 engages with the highest portion of the external cam 3a of the amplitude limiting cam 3, thereby adjusting the amplitude of the needle bar. is maintained at zero, allowing for tacking stitches.
By simply turning on one manual operation member 52, the amplitude becomes zero and the feed is reversed. Especially when making buttonholes, unlike other cases, the forward line is changed. This is a device that can be used to tack stitches, and is an extremely effective invention in practical terms.

[Brief explanation of the drawing]

FIG. 1 is an external view of a sewing machine incorporating a device according to the present invention;
Fig. 2 is a front view of the device according to the present invention, Fig. 3 is an explanatory diagram of the operation of the amplitude limiting cam, Fig. 4 is an explanatory diagram of the operation of the feed reversal mechanism, and Fig. 5 is an explanatory diagram of the operation of the amplitude conversion mechanism. , Fig. 6 is an explanatory diagram of the operation of the feed reversal mechanism section during buttonhole sewing, and Fig. 1 shows the amplitude limiting cam 3, where A is a front view and B is a
C is a left side view of A, D is a developed view of the side cam part, FIG. 8 is a cross-sectional view of the bevel gear 7, FIG. 9 is a cross-sectional view of the clutch ring 8, B is a right side view of A, and C is a left side view of A. In the figure, 3 is an amplitude limiting cam, 13 is an amplitude adjustment arm, 23 is a solenoid, 31 is an operating arm, and 53 is a return spring.

Claims (1)

[Claims] 1 Solenoid 2 mounted on a mechanical stand fixed to the sewing machine arm and activated by operation of one manual operation member 52
3, a feed reversing mechanism 28 that changes the feed phase by 180° in conjunction with the solenoid to reverse the feed, and a shaft 4 fitted in the mechanism base and rotatably supported by the sewing machine arm. A bevel gear 7 that rotates in conjunction with the main shaft, an external cam 3a, a side cam 3b, and a protrusion 3c fitted on the shaft 4.
an amplitude limiting cam 3 formed with a recess 8a that is fitted on the shaft 4 between the bevel gear 7 and the amplitude limiting cam 3 and that can engage with the protrusion 3c of the amplitude limiting cam; A recess 8b that can engage with a protrusion 7a formed on the gear 7
The clutch ring 8 is fitted onto the shaft 14 fixed to the mechanism base, and has a claw portion 13a at one end that can be engaged with the external cam 3a of the depression limiting cam 3, and the other end is fitted onto the needle bar. an amplitude adjusting arm 13 connected to the needle bar to adjust the amplitude of the needle bar, and a pin 31a fitted to a shaft 32 fixed to the mechanism base and capable of pressure-engaging with the side cam 3b of the amplitude limiting cam 3 at one end. An actuating arm 31 is implanted and operates in conjunction with the solenoid 23, and a return force is applied to the amplitude limiting cam 3 so that the protrusion 3c of the amplitude limiting cam 3 engages with the recess 8a of the clutch ring 8. A clutch spring 54 is provided with a spring 53 and a clutch spring 54 which is biased against the clutch ring so that the spring pressure is smaller than the spring pressure of the return spring and the protrusion 7a of the bevel gear 7 and the recess 8b of the clutch ring 8 are disengaged, By turning on the solenoid 23, the feed reversing mechanism 28 is actuated to reverse the feed, and the operating arm 31 is engaged with the side cam 3b of the amplitude limiting cam 3 to change the amplitude of the amplitude limiting cam. The projection 3c of the limiting cam is moved in the axial direction so that the engagement with the recess 8a of the clutch ring 8 is disengaged, and the claw portion 13a of the amplitude adjusting arm 13 is moved to the highest part of the external cam 3a of the amplitude limiting cam 3. A tacking device for a sewing machine, characterized in that the tacking device for a sewing machine is configured so that tacking can be performed while the amplitude of the needle bar is maintained at zero when the needle bar is engaged.