JPS622833B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a sewing machine mechanism.

In particular, it can be connected to a mechanism that intermittently approaches and separates from a rotating body that is continuously rotating due to the power of a drive source, and receives a force acting in one direction at all times, such as a device that moves a presser foot up and down. This is what activates the mechanism.

As an embodiment of the present invention, the one shown in the drawing is a cycle stitch sewing machine such as a bar-tack stitch, which is started by pulling the start lever, and after forming a certain number of stitches, the start lever automatically returns to its original position and stops. This is applied to a presser foot vertical movement device.

As shown in FIG. 1, the base plate 2 provided on the upper surface of the bed 1 is linked to the sewing machine mechanism and slides from side to side in a predetermined manner and rotates around the right end, and the base plate 2 is attached to the tip of the base plate 2, which is sewn with the sewing machine and spread downward. The support 3 is fixed, and the bent base of the support arm 4 is fixed to the upper surface of the substrate 2.

At the tip of the support arm 4, a vertical part of a presser foot 5, which has a flat portion that matches the upper surface of the cloth support 3, is supported vertically and slidably. The presser foot 5 engages with the tip of the press plate 8, which is rotatable by a step screw 6 and always receives a counterclockwise rotational force due to the action of a spring 7.
always receives a downward force and moves up and down as the pressing plate 8 rotates.

A support stand 10 having a front-back horizontal pin 9 at its tip is fixed to the upper part of the press plate 8, and is provided so that the presser foot 5 moves up and down via the press plate 8 as the support stand 10 moves up and down. .

Inside the arm 11, each right end is connected to the horizontal axis 1.
Horizontal links 14, 16 supported by 2, 13
A vertical link 15 is provided, the upper end of which is pivotally connected to the left end of the horizontal link 16, and the middle part is pivotally connected to the left end of the horizontal link 14 to enable vertical movement. 15
The lower end of the press plate 8 contacts the horizontal pin 9 of the support base 10 to rotate the press plate 8 clockwise against the elastic force of the spring 7.

The upper end of the vertical link 17 is fixed to the horizontal shaft 13,
As a result of this rotation, the horizontal shaft 13 loosely supported by the arm 11 is rotated, and the horizontal link 16 fixed to the horizontal shaft 13 is rotated in the same direction as the vertical link 17. Pivotally attach the left end of 18.

The right end of the connecting plate 18 has a stepped screw 1 inside the arm 11.
L-shaped rotating link 2 rotatably supported by 9
The rotation link 20 is connected to the upper end of the arm 11 and connected to the upper end of the connecting plate 18, and is always subjected to a counterclockwise rotational force via the connecting plate 18 due to the spring 21 provided between the arm 11 and the connecting plate 18. At the right end of the rotation link 20,
The upper end of the movable plate 22 is connected so that the upper end surface and the lower end surface are twisted at approximately 90 degrees.

In the mechanism shown in FIG. 1, when the rotating link 20 rotates clockwise, the connecting plate 18 moves to the right, rotates the vertical link 17 counterclockwise, and connects the vertical link 15 via the horizontal link 16. As it descends, its lower end contacts the horizontal pin 9 and pushes the horizontal pin 9 downward, pushing down the support base 10, rotating the press plate 8 clockwise and lifting the presser foot 5 from the upper surface of the cloth support 3. let On the other hand, when the rotation link 20 rotates counterclockwise, the vertical link 15 rises and separates from the horizontal pin 9, and the pressing plate 8 rotates counterclockwise due to the elastic force of the spring 7, pushing the presser foot 5 away from the cloth. Press against the top of support 3.

FIG. 2 is a side view of the part incorporated into the control device of the present invention, and FIG. 3 is an exploded perspective view of the main part, with a part of the right side of the arm 11 cut out vertically, and the cutout shown in FIG. Concave groove 2 on the left end surface to cover
3 is fixed to the right side of the arm 11.

An operating shaft 26 having an eccentric cam 25 fixed to one end located in the groove 23 is rotatably supported on the opposing left and right sides of the frame 24.
6 has a cylindrical shaft 27a that is disposed close to the left side of the frame 24 and extends to the right, and two pawls 27b, 27b' having a locking surface clockwise in FIG. 3 on the outer periphery. A cam body 27 protruding from the cylindrical shaft 27 with a 180 degree interval is fixed by a pin 28, and on the right side of the cylindrical shaft 27a is a cylindrical shaft 29a which is in contact with the right end surface of the cylindrical shaft 27a and has the same diameter as the cylindrical shaft 27a. It rotatably supports a rotating body 29 having a rotary body 29 . Although not shown, this rotating body 29 is connected to a driving section.

A right-handed spring 30 is fitted on the outer periphery of the two cylindrical shafts 27a and 29a, and a fastening body 31 is provided on the outer periphery of the left end of the spring 30 with a plurality of slits 31a, and a protrusion is provided on the outer periphery. At the same time, the left end of the spring 30 and the fastening body 31 are fixed to the cylindrical shaft 27a by the locking ring 33 fitted to the outer periphery of the fastening body 31.

A claw 34a is provided on the outer periphery of the right end of the spring 30 between the claw body 32 and the rotating body 29,
A claw body 34 having a pin 35 that engages with the right end of the spring 30 is rotatably fitted on the inner circumferential surface of the spring 30, and the inner circumference of the claw body 34 covers the outer circumference of the spring 30. do. Note that the claw 32a and the claw 34a each have a locking surface that extends counterclockwise.

The rotation link 20 is protruded from the notch of the arm 11, the movable plate 22 is placed in the notch of the arm 11, and a step screw 3 is installed on the right side of the arm 11.
The lower end of the movable plate 22 is pivotally connected to the free end of a rotary plate 37 rotatably supported by a rotary plate 37. A roller 38 is provided on the side surface of the rotary plate 37, and the upper surface of the roller 38 is rotated by the elastic force of the spring 21. Moving link 20, moving plate 2
2. It is configured to always come into pressure contact with the lower outer circumferential surface of the eccentric cam 25 via the rotary plate 37.

An L-shaped link 40 is rotatably supported by a step screw 39 on the left side of the frame 24, and a coil spring 41 is attached to the left side of the frame 24.
is wrapped around the L-shaped link 40, and one end is locked to a pin 42 protruding from the inside of the left side of the frame 24, and the other end is locked to a pin 40a protruding from the left tip of the L-shaped link 40. By this, L-shaped link 4
The right end of the cam body 27 is pressed against the outer circumferential surface of the cam body 27, and as the cam body 27 rotates clockwise, the claws 27b, 27
b' to prevent its rotation. As shown in FIG. 4, the protrusions 43 and 44 formed in the frame 24 are connected to the bases of a pair of actuation levers 45 and 46, which are opposed to each other with the actuation shaft 26 in between and are arranged substantially parallel to each other. , 48, and is rotatably supported by actuating levers 45, 46.
are connected by a connecting link 49, so that when one operating lever 45 moves in the vertical direction, the other operating lever 46 follows this and moves in the vertical direction. A locking body 52 that can be moved and locked in the left and right directions is fixed to the free end of one of the operating levers 45 by a screw 51 that is loosely fitted into a long hole (not shown) in the right and left directions. In addition to providing a vertical protrusion 52a, the actuating lever 45
A spring 50 is stretched between the frame 24 and the actuating lever 45 to constantly apply a downward force to the operating lever 45. A locking body 52 is provided at the free end of the other actuating lever 46.
A locking body 53 facing the locking body 53 is fixed by a screw 54 loosely fitted into a long hole (not shown) in the right and left direction, and the locking body 53 has a protrusion 53a facing the protrusion 52a of the locking body 52. The actuating lever 46 is provided with a tip 47A at its tip.

The spring 55 has a stronger traction force than the spring 50, and has one end supported by the arm 11 and the other end locked to the actuating body 56, and an actuating plate 57 that extends horizontally from the actuating body 56 and is bent to form a flat portion 57a. 47A is usually pushed upward, and the protruding portion 53a of the locking body 53 is pressed against the claws 32a, 34a of the claw members 32, 34.
configured to engage with. The lower end of the actuating body 56 is connected to a foot pedal (not shown) via a chain 58, and when the foot pedal is depressed, the actuating body 56 is pulled downward against the elastic force of the spring 55.

The operation of this invention having the above configuration will be explained.

When the actuating body 56 is not operated, the protrusion 53a of the locking body 53 touches the claw body 3 as shown by the solid line in FIG.
The locking body 5 engages with the claws 32a and 34a of 2 and 34.
The second protrusion 52a is located outside the rotation locus of the claws 32a and 34a. Then, the pin 35 provided on the claw body 34 stops, and the right end of the spring 30 engages with this pin 35, causing the cylindrical shaft 29a of the rotating body 29 and the cam body
The spring 3 wrapped around the outer peripheral surface of the cylindrical shaft 27a of 7.
0 is loosened, a gap is created between the inner peripheral surface of the spring 30 and the outer peripheral surface of the cylindrical shaft 29a of the rotating body 29, and as a result, the rotating body 29 idles and rotation transmission to the operating shaft 26 is cut off. In order to maintain the slack of 30,
The claw 27 of the cam body 27 fixing the left end of the spring 30
The right end of the L-shaped link 40 engages with the cam body 2.
7 is stopped to prevent the spring 30 from unwinding due to its own contraction force.

At this time, the eccentric cam 25 provided on the operating shaft 26 stops its maximum eccentric portion upward, as shown in FIG. Since the movable plate 22 is in the raised position via the plate 37, the cloth presser foot 5 is pressed against the upper surface of the cloth support 3. From this state, step on the foot pedal (not shown) to release the spring 55.
When the actuating body 56 is moved from the position shown by the solid line in FIG. 4 to the position shown by the two-dot chain line against the elastic force of Due to the elastic force of 50, it rotates from the position indicated by the solid line in Fig. 4 to the position indicated by the two-dot chain line,
The protrusion 53a of the locking body 53 is disengaged from the claws 32a, 34a, and the protrusion 53a of the locking body 53 is disengaged from the claw 32a.
While moving out of the rotation locus of the claws 32a and 34a, the protrusion 52a of the locking body 52 advances into the rotation locus of the claws 32a and 34a. Projection portion 53a of locking body 53
Since the engagement between the claws 32a and 34a is disengaged, the claw body 34 rotates due to the contraction force of the spring 30, and the pin 3
5 and the right end of the spring 30 are disengaged, and the spring 30
is tightened, and since the left end of the spring 30 is fixed to the cylindrical shaft 27a of the cam body 27, the rotating body 29
Due to the frictional resistance between the cylindrical shaft 29a and the outer circumferential surface of the cylindrical shaft 27a of the cam body 27, the spring 30 is further tightened and tightly wound around the outer circumferential surface of the cylindrical shafts 27a and 29a. The actuating shaft 26 is rotated integrally through the actuating shaft 26. At this time, the right end of the L-shaped link 40 separates from the locking surface of the claw 27b of the cam body 27. The claws 32a, 34a of the claw bodies 32, 34 rotate with the rotation of the operating shaft 26.
When rotated 180 degrees, the protrusion 52a of the locking body 52 and the claws 32a, 34 are rotated 180 degrees, as shown by the two-dot chain line in FIG.
a is engaged, the right end of the spring 30 is engaged with the pin 35, and rotation transmission of the rotating body 29 to the operating shaft 26 is interrupted. At this time, as shown in FIG. 5B, the eccentric cam 25 rotates 180 degrees and its maximum eccentricity moves from the upper position to the lower position, and due to the movement of the eccentric cam 25, the roller 38 that was in pressure contact with the lower surface is released by the spring. As the movable plate 22 moves downward against the elastic force of the connecting plate 21, the connecting plate 18 moves to the right and lifts the presser foot 5 from the upper surface of the cloth support 3 as described above.

Note that the right end of the L-shaped link 40 is pressed against the outer periphery of the cam body 27 by the elastic force of the coiled spring 41, and the claw 27 of the cam body 27 is rotated by 180° of the cam body 27.
engages b′.

When the foot pedal (not shown) is released, the elastic force of the spring 55 causes the actuating body 56 to return from the two-dot chain line to the position shown by the solid line in FIG.
a to push up the roller 47A against the elastic force of the spring 50, rotate the levers 45 and 46 counterclockwise to return from the two-dot chain line to the solid line position in FIG. The protrusion 52a and the claws 32a, 34
a is disengaged, and the rotation of the rotating body 29 is caused by the rotation of the operating shaft 2.
6 and the protrusion 5 of the locking body 53
3a advances into the rotation locus of the claw parts 32 and 34,
As the operating shaft 26 rotates, the claws 32a and 34a rotate at 180 degrees.
It rotates by .degree. and engages with the protrusion 53a of the locking body 53, thereby cutting off the transmission of rotation of the rotating body 29 to the operating shaft 26. At this time, the presser foot 5 presses the upper surface of the cloth support 3.

The relationship between the operating levers 45, 46 and the claw 34a of the claw body 34 will be explained with reference to FIG. 7. When the operating lever 46 and the claw 34a are engaged, the operating lever 46
The rotation fulcrum is A, the engagement point between the protrusion 53a of the locking body 53 and the base of the claw 34a of the claw body 34 is D, and the engagement point between the protrusion 53a and the tip of the claw 34a of the claw body 34. Let be F, and make sure that A, D, and F are at right angles. When the claw body 34 rotates counterclockwise and hits the protrusion 53a of the locking body 53 provided on the operating lever 46, the force of the claw body 34 acting in the direction perpendicular to D and F is due to the force of the claw 34a. At the base (point D in Figure 7),
Since it works in the D and A directions and does not produce any force component in the other direction, the actuating lever 46 is in a stationary state and the claw 34a
securely locks onto the protrusion 53a of the locking body 53 without bouncing. Thereafter, the actuation lever 46 rotates counterclockwise and the protrusion 53a of the locking body 53 is rotated.
When is removed from the claw 34a, since A and D are shorter than A and F, the arc formed by A and D is AF.
The claw 34a of the claw body 34 is located inside the arc according to
is smoothly separated without being pushed back in the direction opposite to the rotating direction of the claw part body 34.

Further, the claw body 34 rotates 180 degrees around the point P, and rotates from the position indicated by the solid line to the position indicated by the two-dot chain line.
When the actuating lever 45 is engaged with the protrusion 52a of the locking body 52, the pivot point of the actuating lever 45 is set at B,
The protrusion 52a of the locking body 52 and the claw 34 of the claw body 34
Engagement point C with the tip of a, protrusion 5 of locking body 52
The engagement point between 2a and the base of the claw 34a is E, B,
Make C and E at right angles. When the claw 34a of the claw body 34 hits the protrusion 52a of the locking body 52,
The force of the claw body 34 acting in the direction perpendicular to C and E is as follows at the tip of the claw 34a (point C in Figure 7):
Since the actuation lever 45 acts in the C and B directions and does not generate any component force in the other direction, the actuating lever 45 is in a stationary state and the claw 34a
The protruding portion 5 of the locking body 52 of the actuating lever 45 will not bounce and come off the locking body 52 of the actuating lever 45.
2a. Thereafter, the actuating lever 45 rotates clockwise and the protrusion 52a of the locking body 52 engages the claw 3.
When it comes off from 4a, since B and C are shorter than B and E, the circular arc formed by B and C is inside the circular arc formed by B and E, and the claw 34a is surely separated without being pushed back.

Conventionally, as a control device for this type of sewing machine mechanism,
As shown in FIG. 6, two locking portions 60 and 61 which are opposed to each other with the axis of the actuating shaft in between are formed by the actuating lever 59.
When the operating lever 59 moves in one direction and in the opposite direction, one of the locking parts 60 and 61 enters into the rotation locus of the claw 34a of the claw body 34, and the claw body 3
In the case where the rotation of the claw body 34 is stopped by engaging with the claw 34a of No. 4, the base shaft 59 of the operating lever 59
Since the axis of a is provided between the engaging parts 60 and 61 of the actuating lever 59, when the pawl 34a engages with the engaging parts 60 and 61 of the actuating lever 59, the actuating lever 59 receives an elastic force. bounces and claws 34
When the claw 34a is released from the locking parts 60, 61 of the operating lever 59, the claw 34a
In order to prevent the tip of a from being pushed back in the direction opposite to the rotation of the claw body 34, the engaging surfaces of the locking parts 60, 61 of the actuating lever 59 are inclined with respect to the arms of the actuating lever 59. The machining work is difficult because it has to be a flat surface, and even if there is a slight error,
When the pawl 34a is released from the locking portions 60, 61 of the operating lever 59, it is pushed back, which increases frictional resistance and imposes an extra load, which increases the effort required by the operator to press the foot pedal. .

The purpose of this invention is to eliminate the above-mentioned drawbacks, and the purpose of this invention is to disengage the locking body of one operating lever and the claw of the claw body by pulling the foot plate or the like and releasing the same. A sewing machine mechanism that uses the power of a drive source to receive a force acting in one direction, such as with an elastic force, like a presser foot, until the pawl engages the locking body of the other operating lever. When one of the actuating levers engages the pawl body at its locking part, the actuating lever's side opposite to the engaging surface of the pawl is The base has a rotational fulcrum, and the plane passing through the rotational fulcrum and the base of the engagement surface of the pawl is approximately perpendicular to the engagement surface of the pawl. When the lever comes off and rotates half a turn, and the other operating lever engages with the pawl body at its locking part, the rotation fulcrum of the base of the actuating lever is on the opposite side of the engaging surface of the pawl, and the rotation The locking body 5 of the operating levers 45 and 46 is provided at a position where the plane passing through the fulcrum and the tip of the engaging surface of the pawl is substantially orthogonal to the engaging surface of the pawl.
2, 53 may be made into a block body whose engaging surfaces are perpendicular to the plane passing through the axes of the base shafts of the operating levers 45, 46, and machining is simple and machining work is facilitated. When the pawl 34a of the body 34 engages with the locking bodies 52, 53 of the actuating levers 45, 46, the actuating levers 45, 46 bounce and the pawl 3
4a is the locking body 52, 53 of the operating lever 45, 46
The pawl 34a is attached to the actuating lever 4 without coming off.
5, 46, and the pawl 34a is securely engaged with the locking bodies 52, 53 of the operating levers 45, 46.
2, 53, the pawl 34a is smoothly removed without being pushed back, thereby reliably reducing the load on the control of the sewing machine mechanism, making it easier for the operator to press down on the treadle, etc., and reducing operator fatigue. This is effective in improving work efficiency.

In addition, in the above embodiment, the actuation levers 45, 4
6 are connected by a connecting link 49, and the other actuating lever 46 follows the vertical movement of one actuating lever 45 and interlocks with it. The claw body 34 is provided in a sandwiched manner, and the claw body 34 is attached separately depending on the time.
It may be configured to engage with the claw 34a of.

[Brief explanation of the drawing]

Fig. 1 is a front view of the sewing machine showing the sewing machine presser foot vertical movement mechanism, Fig. 2 is a partial front view of the rear part of the sewing machine incorporating the sewing machine control device, and Fig. 3 is the
Fig. 4 is an exploded perspective view of the main parts of the control device shown in Fig. 4, Fig. 4 is an action explanatory diagram showing the traction operation of the sewing machine, Figs. 5A and 5B are action explanatory diagrams, and Fig. 6 shows the main parts of the conventional embodiment. . FIG. 7 is an explanatory diagram of the operation.

Claims (1)

[Claims] 1. An operating shaft 26 rotatably supported on a frame.
A rotating body 29 that is rotatably supported around an operating shaft in conjunction with a drive source and has a cylindrical shaft, and a cam 27 that has a cylindrical shaft with the same diameter as the cylindrical shaft of the rotating body and is fixed to the operating shaft. a spring 30 formed in a spiral shape and arranged so that the inner peripheral surface of one end is frictionally engaged with the outer periphery of the cylindrical shaft of the rotating body, and the other end is fixed to the cylindrical shaft of the cam body; and the outer periphery of the spring. One end of the spring when its own rotation is locked on the inner periphery. A pawl body 34 is provided with a pin for engaging with the inner circumference of the spring and releasing the frictional engagement between the inner circumference of the spring and the outer circumference of the cylindrical shaft of the rotating body, and the claw body 34 is arranged to sandwich the operating shaft and rotates around the base of the frame. While being freely supported, one side moves out of the rotational trajectory of the claw body and the other enters the rotational trajectory of the claw body and locks with the claw of the claw body due to movement in one direction and the opposite direction. A plurality of actuating levers 45 and 46 are provided with locking portions at their free ends and are arranged substantially parallel to stop the rotation of the body, and a mechanism that receives an acting force in one direction is associated with the mechanism. In a device operated by an actuating shaft, when one of the actuating levers engages with the pawl body at its locking portion, the pivot point of the base of the actuating lever is on the side opposite to the engaging surface of the pawl, and The rotational fulcrum and the plane passing through the base of the engagement surface of the pawl are located at a position that is almost perpendicular to the engagement surface of the pawl, and the pawl body detaches from one actuation lever and rotates half a turn, causing the movement of the other actuation lever. When the locking part engages with the pawl body, the rotational fulcrum of the base of the operating lever is on the opposite side of the engaging surface of the pawl, and the rotational fulcrum and the tip of the engaging surface of the pawl are located on the opposite side of the engaging surface of the pawl. A control device for a sewing machine, characterized in that the plane passing through is provided at a position substantially perpendicular to the engaging surface of the pawl.