JPS623113Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a lifting device for a presser foot in a cycle sewing machine.

Figure 1 shows a conventional system in which the presser foot (not shown) is manually raised and lowered.When the control lever 1 is rotated counterclockwise around a shaft 2 fixed to the sewing machine frame, the motor and main shaft of the sewing machine are connected via a clutch to drive the needle bar of the sewing machine, and when the presser foot lifting lever 3 is rotated clockwise about the shaft 3A supported on the frame 4, the connecting link 5 moves downward and the sliding plate By pushing down the roller 6A supported by the roller 6, the sliding plate 6 is moved downward, and the presser foot interlocked with the sliding plate 6 is raised.

In order to prevent the presser foot lifting lever 3 from operating while the needle bar of the sewing machine is being driven, a locking rod 7 is provided with one end fixedly supported on the control lever 1 and the other end extending below the sliding plate 6. When the control lever 1 rotates counterclockwise, the locking portion 7a of the locking rod 7 moves to the left and engages with the lower part of the sliding plate 6, thereby lifting the presser foot lever 3.
When the presser foot lifting lever 3 is operated, the sliding plate 6 is lowered to prevent the locking rod 7 from moving to the left, thereby preventing the control lever 1 from operating. It's getting old.

However, since the locking rod 7 has a relatively long structure, when the operator strongly rotates the control lever 1, the locking rod 7 bends and disengages from the sliding plate 6, causing the presser foot to rise. There was a risk that the needle bar of the sewing machine would be driven or the locking rod 7 would break.

The object of this invention is to provide a presser foot lifting device for a cycle sewing machine that can eliminate such drawbacks.

An embodiment of this invention will be described below based on the drawings.

2 and 3, reference numeral 10 denotes a drive belt that interlocks the drive motor 11 of the sewing machine and a pulley 12 connected to the main shaft (not shown) of the sewing machine via a clutch (not shown); 10 in FIG. 4; A presser foot is supported on the machine frame so as to be movable horizontally on the bed surface 14 back and forth and left and right in conjunction with the main shaft, and is movable up and down on the machine frame. 16 is the presser foot 1 as shown in FIG.
3 and a link mechanism 17, the moving body is vertically movably supported on the machine frame, and a roller 17a is rotatably supported. Reference numeral 18 denotes a control lever rotatably supported on the machine frame. When the control lever 18 is rotated counterclockwise, the main shaft of the sewing machine is linked with the motor, the needle bar 19 moves up and down, and the presser foot 13 moves back and forth. When the control lever 18 is moved in the left-right direction and returned to its original position by the elastic force of the spring, the interlock between the main shaft of the sewing machine and the drive motor 11 is cut off.

Reference numeral 20 denotes an engaging portion formed below the control lever 18.

Reference numeral 21 indicates a first presser foot lifting device that moves the presser foot 13 up and down by human power, 22 a first frame body that can be attached to and detached from the machine frame with screws 23, 23, 23, and 24 a first frame body. Shaft 25 supported below body 22
A presser foot lifting lever with one end rotatably supported.
A long hole 27 is opened in the middle part of the presser foot lifting lever 24, and the long hole 27 can be loosely fitted into the roller 17a of the movable body 17.

Reference numeral 28 denotes a rotating arm whose intermediate portion is rotatably supported on a shaft 29 supported above the first frame 22, and has an arcuate curved surface portion 28A at its free end, and a link 30 at the other end. It is connected to the presser foot lifting lever 24 via the presser foot lifting lever 24. Then, when the presser foot lifting lever 24 is rotated clockwise, the movable body 16 moves downward, and the presser foot 13, which is in the lowered position, is raised via the link mechanism 17. At the same time, the rotating arm 2 is connected via the link 30.
8 rotates clockwise around the shaft 29 to rotate the rotating arm 2.
8 curved surface portion 28A is the engaging portion 20 of the control lever 18.
, and prevents the control lever 18 from moving counterclockwise. In addition, at this time, the rotating arm 2
The above-mentioned shaft 29 is
is provided on the line of action of the force exerted by the control lever 18 on the rotating arm 28.

31 is a first rotatably supported on the first frame 22;
The pulley engages with the drive belt 10 to rotate.

32 is a Mydra pulley rotatably supported below the first frame 22.

FIG. 3 shows a second presser foot lifting device 3 that uses the power of the drive motor 11 to move the presser foot 13 up and down.
3 shows a sewing machine equipped with the following.

In the figure, 34 is a second frame detachably attached to the machine frame with screws 35, and 36 is a second frame 34.
The second pulley is rotatably supported by the second pulley, and is adapted to rotate when engaged with the drive belt 10.

37 is a spring clutch equipped with a known claw body 37A as shown in Japanese Patent Publication No. 52-29213, etc.;
An eccentric cam 38 is rotatably connected to the second frame 34 via the spring clutch 37. The eccentric cam 38 is arranged so as to come into contact with the roller 17a of the moving body 17.

39 is an operating lever rotatably supported on the second frame 34, which is normally connected to the second pulley 36 and the eccentric cam 3.
The spring clutch 37 acts on the spring clutch 37 to guide the presser foot to the lowered position by cutting off the interlock with the second pulley 36.
The spring clutch 37 is operated in conjunction with the eccentric cam 38 to guide the presser foot 13 to the raised position.

Note that 39 is an idler pulley rotatably supported below the second frame 34.

Next, the operation of this invention will be explained.

First, the sewing machine to which the first presser foot lifting device 21 is attached will be explained.

The state shown in FIG. 6 shows a state in which the drive motor 11 and the main shaft of the sewing machine are disconnected, the sewing machine is stopped, and the presser foot 13 is lowered.

From this state, the operator first moves the presser foot lifting lever 2
Rotate clockwise. Then presser foot lifting lever 2
The movable body 16 loosely fitted into the elongated hole 27 of 4 is pushed down and the presser foot 1
3 rises. Next, the fabric to be sewn is inserted between the bed surface and the bed surface.

At the same time, the rotating arm 28 rotates clockwise around the shaft 29 via the link 30, and the curved surface portion 28A of the rotating arm 28 moves to a position facing the engaging portion 20 of the control lever 18, thereby controlling the control lever. Prevents the lever 18 from moving counterclockwise.

Therefore, if the presser foot 13 remains raised, the control lever 18 will not operate, and the presser foot 13 will not move back and forth, and the needle bar will not move up and down.

When the rotation of the presser foot lifting lever 24 is released from this state, the presser foot lifting lever 24 is rotated counterclockwise by the elastic restoring force of the spring S, the movable body 16 moves upward, and the presser foot 13 descends. The fabric to be sewn is clamped between the 14 sides of the bed. At the same time, the rotating arm 28 rotates counterclockwise about the shaft 29 via the link 30, and its curved surface 28A separates from the position facing the engaging portion 20 of the control lever 18.

Thereafter, when the control lever 18 is rotated counterclockwise, the control lever 18 is positioned above the rotary arm 28, thereby preventing the rotary arm 28 from rotating clockwise. The operation of the lifting lever 24 is inhibited to prevent the presser foot 13 from rising, and the main shaft and drive motor 11 are linked to move the needle bar up and down, and the presser foot 13 moves back and forth and left and right to raise the workpiece. form a cycle seam.

Next, in order to install the second presser foot lifting device 33 in place of the first presser foot lifting device 21, first screws 23, 23,
23 from the machine frame and remove the first presser foot lifting device 2.
1. Remove the entire unit from the machine frame. After that, the second frame 34 of the second presser foot lifting device 33 is attached with screws 35, and the second pulley 36 is passed around the drive belt 10, and the drive belt 10 is also passed around the idler pulley 39. In this way, the work of replacing the first presser foot lifting device 21 with the second presser foot lifting device 33 does not require replacing the belt, so the working time can be significantly shortened.

FIG. 3 shows a sewing machine equipped with a second presser foot lifting device 33. In this state, the drive motor 11 and main shaft of the sewing machine are cut off, the sewing machine is stopped, and the presser foot 13 is lowered. .

When the operator rotates the actuating lever 39 clockwise from this state, the spring clutch 37 is moved from the second pulley 37, which is constantly rotated by the drive motor 11.
and the eccentric cam 38, and when the eccentric cam 38 rotates half a rotation, the interlock between the second pulley 36 and the eccentric cam 38 is interrupted by the spring clutch 37, and the eccentric cam 38 moves the movable body 16 downward via the rollers 17a. As a result, the presser foot 13 moves upward via the link mechanism 17.

Then, when the operator releases the rotational force of the operating lever 39 after inserting the fabric to be sewn between the bed surface and the presser foot 13, the operating lever 39 is rotated counterclockwise by the elastic force of the spring. .

As a result, the spring clutch 37 again interlocks the second pulley 36 and the eccentric cam 38, and as the eccentric cam 38 rotates half a turn and returns to its original position, the movable body 16 moves upward. The presser foot 13 descends and clamps the fabric to be sewn between it and the bed surface.

Thereafter, when the control lever 18 is rotated counterclockwise, the main shaft and drive motor 11 are linked to move the needle bar up and down, and the presser foot 13 moves back and forth and left and right to form cycle stitches on the fabric to be sewn. do.

As described above, according to this invention, the control lever is configured to prevent malfunction of the control lever or malfunction of the rotary arm itself by rotating the rotary arm rotatably supported on the machine frame. Even if the operator strongly rotates the lever, there is no risk of the rotating arm being bent by the rotating force.

Therefore, the needle bar of the sewing machine is no longer driven while the presser foot remains raised, which improves worker safety and eliminates malfunctions, resulting in improved work efficiency.

[Brief explanation of the drawing]

Figure 1 is a front view of a conventional presser foot lifting device, Figure 2 is a front view of a conventional presser foot lifting device;
Fig. 6 is a front view of the presser foot lifting device according to this invention, Fig. 3 is a front view of the presser foot lifting device of Fig. 2, and Fig. 4 shows the presser foot and link mechanism according to this invention. FIG. 5 is a front view, FIG. 5 is a partial sectional view of the link mechanism according to this invention, and FIG. 7 is a partial sectional view of the presser foot lifting device shown in FIG. 2. 10... Drive belt, 13... Presser foot, 18
...control lever, 20...engaging portion, 21...first
Presser foot lifting device, 24...Presser foot lifting lever, 28...
...Rotating arm, 31...First pulley, 33...Second
Presser foot lifting device, 34... second frame body, 36... second
Pulley, 37...spring clutch, 38...eccentric cam.

Claims (1)

[Claims for Utility Model Registration] The device is rotatably supported on the machine frame, and is normally moved to a position where the interlock between the drive source and the main shaft is cut off by elastic force, and the drive source is connected to the main shaft by rotating against the elastic force. A control lever that moves to a position that interlocks with the main shaft, and a presser foot that moves horizontally on the bed surface back and forth and left and right in conjunction with the main shaft. a movable body supported on the control lever; an engagement portion formed below the control lever; and a movable body rotatably supported on the machine frame and engaged with the movable body to raise the presser foot and lower the presser foot. and a presser foot lifting lever that is movable between the presser foot and the presser foot lifting lever, which is moved away from the movement path of the engaging portion to resist the elastic force of the control lever. In connection with the presser foot lifting lever being positioned at a position that allows rotation and raises the presser foot, the machine frame is arranged so that it faces away from the movement path of the engaging portion and prevents rotation of the control lever. A device for lifting and lowering a presser foot in a cycle sewing machine, comprising a rotating arm that is rotatably supported by the presser foot and is linked to a presser foot lifting lever.