JPS5922549B2 - Spindle manual drive device in sewing machine equipped with single stitch actuation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a main shaft manual drive device for a sewing machine equipped with a single stitch actuating device, and particularly relates to a manual drive device for a main shaft in a sewing machine equipped with a single stitch actuating device. The stop lever, one end of which is normally positioned due to the action of the spring, is rotated by the actuation of the actuating means, and one end of the stop lever is once moved out of the rotation locus of the engaging portion, and then immediately the stop lever is moved under the action of the spring. Regarding a sewing machine equipped with a single stitch actuating device configured to stop the main shaft of the sewing machine after one revolution by returning to its original position, the sewing machine can form only one stitch. When the band wheel is rotated to manually rotate the main shaft of the sewing machine, the engagement between the stop lever and the engaging portion of the rotating member is automatically disengaged, and the presence of the needle line actuating device automatically disengages the stop lever from the engaging portion of the rotating member. However, it is an object of the present invention to provide a main shaft manual drive device which allows the main shaft to be rotated freely manually without any hindrance.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an apparatus embodying the present invention will be described below with reference to the drawings.

First, referring to Figures 1 to 4, 1 is the sewing machine frame 2.
A main shaft 3 is supported by a pulley into which a shaft cylinder 4 is inserted, which is connected to an electric motor via a belt 5 and rotated together with the shaft cylinder 4 around the main shaft 1 .

Reference numeral 6 denotes a second shaft cylinder adjacent to the shaft cylinder 4, which is inserted and fixed to the main shaft 1, and has an outer diameter equal to that of the shaft cylinder 4.

Reference numeral 7 denotes a cylindrical helical spring tightly wound around both shaft tubes 4 and 6, and one end 7a located on the first shaft tube 4 side is erected radially outward. is locked to a rotating member or sleeve 8 fitted around the other end 7.
b is a cut groove 6.b bored in the 20th shaft cylinder 6; a (6th
(see figure).

Therefore, the rotation of the pulley 3 is always caused by the rotation of the first shaft cylinder 4,
is transmitted to the main shaft 1 via the helical spring 7 and the second shaft cylinder 6,
In addition, when one end 7a of the helical spring 7 is locked by some means, the helical spring 7 is relaxed, the rotation of the pulley 3 is not transmitted to the main shaft 1, and the main shaft 1 is stopped. The helical spring 7 acts as a clutch spring.

Further, 9 is another cut groove 5b bored in the second shaft cylinder 6.
, 5b are fitted with a pair of cut-and-raised portions 9a, 9a to form the main shaft 1.
The mounting plate 10 is inserted and fixed onto the main shaft 1 with a fixing screw 11, and its inner end presses the mounting plate 9, so that the mounting plate 9 and the collar 10 It acts to be fixed integrally with the main shaft 1.

Reference numeral 12 indicates a band wheel which is loosely fitted into the cylindrical portion of the flange collar 10 and is rotatably located between the flange portion and the mounting plate 9; 13 indicates a band wheel between the band wheel and the mounting plate 9; A tensioned tension spring (see FIG. 4) urges the band wheel 12 against the main shaft 1 in a direction opposite to its normal rotation direction.

Furthermore, 14 is a pair of leg portions 9 b and 9 of the mounting plate 9.
The operating arm is movably attached to c via a pair of links 15 and 16, and its outer edge 14a is formed in an arc shape, and a recess 14b is formed inside the middle part by a pair of protrusions. Engaging portions 14c and 14d facing the band wheel 12 are formed at the tips of the projections.

The mounting plate 9, the link 15° 16, and the operating arm 14 form a four-joint rotating chain, and the protrusion 12a protruding from the band wheel 12 fits into the recess 14b of the operating arm 14. The operating arm 14 is moved by the action of the spring 12 which urges the band wheel 12 in the direction opposite to the direction of the arrow, and as shown in FIG. It is held in that position by engaging with one side edge of one leg 9b of.

Also, in that position, the outer edge 14a of the actuating arm 14
is located relatively inward in the radial direction of the main axis,
As shown in FIG. 7, when the operating arm 14 is moved relative to the mounting plate 9 in the direction of the arrow, its outer edge 1
4a is configured to move relatively outward in the radial direction of the main shaft, and when the actuating arm 14 moves in the direction of the arrow with respect to the mounting plate 9, the other engaging portion 14d moves relative to the mounting plate 9. It is regulated by engaging with the side edge of the other leg portion 9c.

Therefore, the operating arm 14 is attached to the mounting plate 9 so that it can move relative to it within a certain range.

On the other hand, reference numeral 17 denotes a stop lever which is pivotally connected to a support plate 18 fixed to the sewing machine frame 2 by a shoulder screw 19, and has one arm so that it can engage with an engaging portion 8a formed in the sleeve 8. an extension part 17b whose tip is located close to the outer edge 14a of the operating arm 14 so as to be able to engage with the outer edge 14a of the actuating arm 14; An engaging portion 17c is formed on the narrow arm, and a bent step portion 1 for guiding the movement of the intermediate lever is formed on the thin arm.
7d is formed.

Reference numeral 20 denotes a tension spring stretched between the stop lever 17 and the support plate 18, which acts so that the one end abutting part 17a of the stop lever 17 is always located on the rotation trajectory of the retaining part 8a. do.

When the contact portion 17a is located on the rotation locus of the engagement portion 8a, the extension portion 17b of the stop lever 17 is positioned at the outer edge 14 of the operating arm 14 at the position shown in FIG.
It is constructed and arranged so as to be close enough to not engage with a.

Moreover, when the abutting portion 17a of the stop lever 17 engages with the engaging portion 8a of the sleeve 8, one end 7a of the helical spring 7 is locked, and the main shaft 1 is stopped, the tip of the thread take-up of the sewing machine The position of the engaging portion 8a is set so that the sewing machine needle is located at approximately the uppermost position, and therefore, the needle bar that supports the sewing machine needle at the lower end stops when it reaches a position slightly lower than the uppermost position.

21 is a second support plate fixed to the sewing machine frame 2 with screws 22; 23 is a screw 2 attached to the bent portion 21a of the support plate 21;
actuating means or electromagnetic solenoid secured by 4, 25;
is an intermediate lever pivotally attached to the plunger 23a of the solenoid 23 by a pivot 27 via a synthetic resin plate 26 (see FIG. 3);
5 and acts as a magnetic insulating plate.

Further, the intermediate portion of the intermediate lever 25 is provided with the stop lever 1.
A claw portion 25a that can be engaged with the engaging portion 17c of the intermediate lever 25 is formed, and the tip of the intermediate lever 25 is connected to the stop lever 17.
It extends so as to face the thin arm of.

Reference numeral 28 denotes a tension spring stretched between the intermediate lever 25 and the support plate 18. As is clear from FIG. It is located on the left side of the line connecting the locking point with the plunger 23a and the center point of the pivot shaft 27, and always urges the intermediate lever 25 upward and rotates around the pivot point with the plunger 23a. It provides rotational force in the direction.

Therefore, one side edge 25b of the intermediate lever 25 engages with the side edge of the bent step 17d of the stop lever 17, and the movement of the intermediate lever 25 is guided.

Further, the guide portion 17e of the stop lever 170 is connected to the intermediate lever 2.
5 from the front in FIG. 2, and restricts the forward movement of the tip of the intermediate lever 25.

Further, 29 is a third support plate fixed to the sewing machine frame 2 by screws 30 and the screws 22, and 31 is pivotally connected to the support plate 29 by step screws 32, and one end thereof is connected to the bent portion 17f of the stop lever 17. The opposing switching lever 33 is attached to the support plate 2 so that one side edge faces the other end of the switching lever 31.
The control lever is pivotally connected to the control lever 9 by a step screw 34, and one arm thereof is formed with an abutting portion 33a that faces an operating protrusion 35a of a changeover switch 35 fixed to the second support plate 21.

Reference numeral 36 denotes a tension spring stretched between the switching lever 31 and the third support plate 29, which has a stronger spring force than the spring 20, and is attached to the switching lever 31 as shown in FIG. Provides clockwise rotational force.

Reference numeral 37 denotes a linking lever which is pivotally connected to the support plate 29 by a shoulder screw 38, and whose one end engages with the extending portion 33b of the operating lever 33. The other end is located at the front of the sewing machine frame 2 and is rotated by the machine frame. It is operatively connected to a movably mounted manual operating knob 39.

In FIG. 1, 40 is a retaining ring for regulating the axial movement of the pulley 3, and 41 is a cover.

Next, the electric circuit in this embodiment will be explained with reference to FIG.

In the figure, reference numerals 42 and 42 are power supply terminals connected to an AC power source, and between these two terminals, there is a diode 43 with the polarity shown, a sewing machine motor 44, and a terminal for controlling the power supply to the motor and the speed of the motor. Controller 4 including variable resistor 45
6 are connected in series to form a motor drive circuit.

47 is a manually operated switch for shorting the diode 43, which is connected in parallel to the diode 43 via the changeover switch 35 to form a short circuit.

Further, the AC input terminal of the bridge rectifier 48, to which the electromagnetic solenoid 23 described above is connected between the output terminals, is connected in parallel to the series circuit of the diode 43 and the sewing machine motor 44 via a changeover switch 35, and is connected to the solenoid operating circuit. It consists of

Accordingly, the changeover switch 35 can be switched to selectively enable the short circuit and the solenoid actuated circuit.

Furthermore, 49 is a lamp connected between the power terminals via a manual switch 50, and the manual switch 50 and the manual operation switch 47 are connected to the second support plate 21, as shown in FIG. The cover 41 is fixed adjacently to the lower end and can be opened and closed from the outside of the cover 41.

The device of this embodiment has the structure described above, and its operating mode will be explained below.

Figures 1 to 6 show the positional relationship when each member is set to a state where it can perform basting stitches with a single needle line.
The operating protrusion 35a of the changeover switch 35 is connected to the operating lever 3.
3, and as shown in FIG. 5, the movable contact a and the fixed contact A of the switch 35 are closed.

When the controller is pressed in this state, the sewing machine motor 4
4 and the electromagnetic solenoid 23.

Therefore, the solenoid 23 is activated immediately and its plunger 23a is sucked downward in FIGS. Claw portion 25
a and the engaging portion 17c of the stop lever 17 causes the lever 17 to rotate around the step screw 19 against the action of the tension spring 20.

Due to this rotation, the abutting portion 17a of the stop lever 17 moves out of the rotational trajectory of the engaging portion 8a of the sleeve 8.

On the other hand, power is supplied to the sewing machine motor 44 to start the motor 44, the pulley 3 rotates together with the shaft cylinder 4 via the belt 5, and the main shaft 1 is started by tightening the helical spring 7.

When the stop lever 17 is rotated by the downward movement of the intermediate lever 25, the bending step 17d presses one side edge 25b of the intermediate lever 25, and the intermediate lever is rotated around the pivot 27. rotate it around.

Therefore, the intermediate lever 25 is rotated while moving downward, and the trajectory of the tip of the claw portion 25a is the sixth.
11 shown in the figure, and on the other hand, since the movement locus of the left end of the engaging portion 17c of the stop lever 17 is a circular arc 12 centered on the axis of the step screw 19, the intermediate lever 25 moves by the suction of the plunger 23a. When the pawl portion 25a moves downward from the intersection point P of both the loci 10 and 12, the engagement with the engaging portion 17c is disengaged, and the stop lever 17 is stopped by the subsequent downward movement of the intermediate lever 25. Nevertheless, it rotates due to the action of the tension spring 20, and its abutting portion 17a returns to the rotation locus of the engaging portion 8a.

As a result, when the engaging portion 8a of the sleeve 8 rotating together with the main shaft 1 reaches the position shown in FIGS. The pulley 3 is relaxed and the driving connection between the pulley 3 and the main shaft 1 is disengaged, and the main shaft 1 is stopped with the balance in the uppermost position.

However, the pulley 3 idles around the main shaft 1 until the pressure from the controller is released, and the electromagnetic solenoid 23 is also in an operating state and held at the lowest position of the intermediate lever 25. The claw portion 25a is located below the engaging portion 17b of the stop lever 17.

Therefore, when the pressure on the controller 46 is released, the power to the electromagnetic solenoid is cut off, and the plunger 23 is cut off.
2 and 6, the intermediate lever 25 returns to its original position as shown in FIGS. 2 and 6 by the action of the tension spring 28.

At that time, the claw portion 25a is attached to the engaging portion 17 of the stop lever 17.
It is clear that c can be easily overcome.

In short, when the controller 46 is pressed, the stop lever 17 rotates against the action of the tension spring 20, and its contact portion 1
7a once moves out of the rotational trajectory of the engaging portion 8a, and at the time of this movement, the main shaft 1 of the sewing machine starts, and then the stop lever 1
7 is rotated back due to the action of the tension spring 20 despite the continuation of the pressing operation of the controller 46, and when the main shaft 1 has made exactly one revolution, the engaging portion 8a abuts against the abutting portion 17a of the stop lever 17. The main shaft 1 is stopped. At this time, the thread take-up is at the uppermost position, the sewing machine needle just reciprocates to form one stitch, and stops above the cloth.

After that, by releasing the pressure on the controller, moving the work cloth by hand, and pressing the controller again, a new stitch is formed in the same manner as described above, and the main shaft 1
By this stitch formation, in other words, by repeating so-called needle stitching, it is possible to perform basting stitches having stitch intervals of arbitrary length.

Furthermore, when performing needle stitching, the helical spring 7 expands when the abutting portion 17a of the stop lever 17 abuts the engaging portion 8a of the sleeve 8, but the sleeve 8 prevents this abnormal expansion. be done.

After that, the stop lever 17 rotates and its abutting portion 17
When a is separated from the engaging portion 8a, the expanded helical spring 7 is immediately tightened, so that the sleeve 8 rotates slightly counterclockwise in FIG. 7.

Therefore, even if the stop lever 17 immediately rotates back, it will not engage with the engaging portion 8a of the sleeve 8 before the main shaft 1 starts, and the main shaft 1 will always make one revolution.

Note that even if the manual operation switch 59 is closed during the basting, the changeover switch 35 is switched to enable the lenoid operating circuit, so the short circuit of the diode 55 is not enabled and the sewing machine motor is not activated. 44 rotates at a relatively low speed.

From the above explanation, it is clear how the basting stitch works,
When the sewing machine is stopped, it may be necessary to manually rotate the main shaft 1 and move the needle bar up and down in order to rotate the work cloth around the sewing machine needle or to pull up the bobbin thread.

In such a case, the apparatus of this embodiment operates as follows.

That is, as shown in FIG.
When the sewing machine is in a state where the sewing machine is stopped by abutting the engagement portion 8a of the sleeve 8, the four-joint rotating chain consisting of the mounting plate 9, the links 15 and 16, and the operating arm 14 is located in the state shown in FIG. Now, when the band wheel 12 is manually rotated in the forward rotational direction of the main shaft 1 against the action of the tension spring 13, the protrusion 12a of the band wheel 12 is prevented from rotating. As a result, the actuating arm 14 moves in the above direction relative to the mounting plate 9, and the link 1
5 and 16 are raised, and the actuating arm 14 also moves outward in the radial direction of the main shaft 10.

Therefore, the outer edge 14a of the actuating arm 14 is connected to the stop lever 1.
By abutting against and moving the extension 17b of 7, the stop lever 17 is rotated against the action of the tension spring 20, and the stop lever 17 comes into contact in the state shown in FIG. The portion 17a disengages from the engagement portion 8a.

The engaging portion 14d of the operating arm 14 comes into contact with the side edge of the leg portion 9c of the mounting plate 9, causing the main shaft 1 to rotate together with the mounting plate 9.

Also, once the main shaft 1 is rotated, the contact portion 8 of the ball sleeve 8
If a rotates counterclockwise from the position shown in FIG. will be activated.

In addition, when rotating the main shaft 1 in the reverse rotation direction, since the reverse rotation side of the engaging portion 8a is formed as an inclined surface, the stop lever 17 can freely rotate without blocking the rotation. It is possible.

Next, a case in which normal continuous stitching is performed will be explained.

First, before suppressing the controller, press the manual operation knob 39.
When the operation lever 33 is rotated to the continuous sewing position, the operation lever 33 is rotated counterclockwise in FIG.
5a is released, and the changeover switch 3 in FIG.
5, the movable contact a and the fixed contact C are closed.

Further, due to the rotation of the operating lever 330, the switching lever 31 is rotated clockwise in FIG. The contact portion 17a of the sleeve 8 is held outside the rotation locus of the engagement portion 8a of the sleeve 8, as shown in FIG.

FIG. 8 shows the positional relationship of each member when the manual operation knob 39 is set to the normal continuous sewing position as described above. When the controller is pressed in this state, power is supplied to the sewing machine motor 44. The motor 44 starts and the belt 5
The boo 93 rotates together with the shaft cylinder 4 via the helical spring 7
is tightened and wrapped around both shaft cylinders 4 and 6, and the pulley 3
The rotation of the main shaft is transmitted to the main shaft 1, and the main shaft starts.

Thereafter, the rotational speed of the motor 44 is controlled by the resistance value of the variable resistor 45, which changes depending on the degree of pressure from the controller, and the speed of the main shaft 1 is arbitrarily adjusted to carry out normal continuous sewing.

At this time, the sleeve 8 fitted around the helical spring 7 also rotates together with the main shaft 1 together with the spring 7, but the abutment part 17a of the stop lever 17 Since it is located outside the trajectory, it does not pose any hindrance to continuous sewing.

At this time, the electromagnetic solenoid 23 does not operate because the aforementioned changeover switch 35 opens the fixed contact C side.

Furthermore, when the controller releases the pressure, the power to the sewing machine motor 44 is cut off, and the main shaft 1 of the sewing machine stops at the sewing position, as in the conventional case.

Further, when the manual operation switch 59 shown in FIGS. 2 and 5 is closed, the diode 43 is short-circuited and the full AC voltage is applied to the sewing machine motor 44.
The electric power supplied to the motor increases compared to when the motor 7 is opened, and its rotational speed increases.

This allows speed control in two modes, high speed and low speed, despite the same degree of suppression by the controller.

As described in detail above, the present invention provides a sewing machine equipped with a needle stitch actuating device, which is provided with a mounting plate 9, a pair of links 15 and 16, and an actuating arm 14 to form a so-called four-bar rotation chain; A main shaft that allows the operating arm 14 to move within a certain range, operatively connects the operating arm 14 and the band wheel 12, and is stopped by engagement between the stop lever 17 and the engaging portion 8a. 1, the actuating arm 14 is moved radially outward of the main shaft to disengage the stop lever 17 from the engaging portion 8a. - Despite the presence of the needle stitch actuating device, the main shaft of the sewing machine can be rotated freely manually without any hindrance, and since the actuating arm operates smoothly due to the four-bar rotation chain, the band wheel It has excellent practical effects, such as being able to rotate easily without making manual rotation operation difficult.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a longitudinal sectional view showing the main parts, Fig. 2 is a front view taken from the line ■-■ in Fig. Right side view seen from the ■-■ line, No. 4
The figures are a sectional view taken along the line IV-IV of Fig. 1, Fig. 5 is an electric circuit diagram, Fig. 6 is a partially enlarged view of Fig. 2, Fig. 7 is a sectional view equivalent to Fig. 4 showing the operating mode, and Fig. 5 is an electric circuit diagram. FIG. 8 is a front view corresponding to FIG. 2 for explaining another operating mode. In the figure, 1 is the main shaft of the sewing machine, 2 is the sewing machine frame, and 8 is the engaging part 8.
a sleeve as a rotating member, 9 a mounting plate, 1
2 is a band wheel having a projection 12a, 13 is a tension spring, 14 is an actuating arm having a recess 14b, 14a is an outer edge, 15 and 16 are a pair of links, 17 is a stop lever having an extension 17b, and 20 is a spring. 23 is an electromagnetic solenoid as an operating means, and 25 is an intermediate lever having a claw portion 25a.

Claims (1)

[Claims] 1 A rotating member 8 having one engaging portion 8a and rotating integrally with the main shaft 1 of the sewing machine, and a rotary member 8 rotatably pivoted to the machine frame 2 of the sewing machine, and one end of which is normally connected to the engaging portion by the action of a spring 200. 8
a stop lever 17 located on the rotational trajectory of the engagement portion 8a; and an actuating means 23 that operates to rotate the stop lever against the action of the spring 200 and move one end thereof out of the rotational trajectory of the engaging portion 8a. When the actuating means is activated, the stop lever 17 is once moved out of the rotation trajectory of the engagement portion 8a, and then the stop lever 17 is returned to the rotation trajectory of the engagement portion 8a by the action of the spring 200. In this sewing machine, a band wheel 12 is loosely fitted to the end of the main shaft 1, and a mounting plate 9 located adjacent to the band wheel is integrated with the main shaft 1. The operating arm 14, whose outer edge 14a is formed in a substantially arc shape, is attached to the mounting plate via a pair of links 15 and 16 so as to be movable within a certain range. A protrusion 12a that also protrudes from the band wheel 12 is fitted into a start 14b formed in the middle of A tension spring 13 is provided which biases the main shaft 1 in the reverse rotation direction, and when the operating arm 14 is located at one end within the movement range via the protrusion 12a due to the action of the tension spring, the outer edge 14a of the main shaft 10 is configured to be located inward in the radial direction, and in a state in which it extends from the stop lever 17 and one end of the stop lever engages with the engaging portion 8a and the main shaft 1 is stopped, the main shaft 1 is located inward in the radial direction. Actuating arm 1 located inward
an extension 17b located close to the outer edge 14a of the actuating arm 1;
4 moves around the main shaft 1 and also moves outward in the radial direction of the main shaft 10, and its outer edge 14a rotates the stop lever 17 out of the rotation locus of the engaging portion 8a against the action of the spring 20. A main shaft manual drive device characterized by being adapted to move the spindle.