JPH088778Y2 - Sewing machine lifting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a presser foot lifting device for a sewing machine.

(Prior Art) As a conventional presser foot lifting device of this type, Japanese Patent Publication No. 60-107
The one shown in Japanese Patent Publication No. 54 is known. This is a rotatable rotation shaft, a movable arm pivotally supported by the rotation shaft and rotated by the operation of an air cylinder, and a lower portion that is linked to the movable arm via a linkage mechanism and moves up and down by the rotation of the movable arm. The presser foot with the presser foot fixed to it, the intermediate arm that is fixed to the rotating shaft and rotates by the operation of the knee pad, and the intermediate arm that is arranged between the movable arm and the intermediate arm Coupling means configured by engagement of a long hole and a pin for integrally rotating the movable arm and the intermediate arm when the knee pad is actuated by rotating the arm relative to each other, and contacting with an oil pan provided on the intermediate arm. It is composed of a bolt capable of adjusting the initial position of the intermediate arm, and the movable arm is rotated by operating the air cylinder, and the rotation of the movable arm raises the presser foot via the linkage mechanism, and Through the middle arm by activating the knee rest In some cases, the movable arm rotates, and the rotation of this movable arm raises the presser foot through the linkage mechanism. By operating a bolt to adjust the initial position of the intermediate arm, the movable arm and the intermediate arm rotate integrally. The amount of rotation of the intermediate arm to the engagement position between the elongated hole and the pin for adjusting is adjusted, and the amount of lift of the presser due to the operation of the knee pad is adjusted.

(Problems to be solved by the invention) However, in the above-described presser foot lifting device for a sewing machine, a long length for integrally rotating the movable arm and the intermediate arm by operating the bolt to adjust the initial position of the intermediate arm. Since the amount of rotation of the intermediate arm to the engagement position between the hole and the pin is adjusted and the amount of lift of the presser foot due to the operation of the knee pad is adjusted, the lift of the presser foot is accurately adjusted each time by the amount of rotation of the knee pad. There was a drawback that the amount of increase did not increase.

Therefore, the present invention has as its technical problem to raise the presser foot with an accurately adjusted amount of lift each time.

[Constitution of device]

(Means for Solving the Problem) The technical means taken in the present invention to solve the above-mentioned technical problem is to restrict rotation of the second operating arm by contacting a stopper formed on the second operating arm. In addition, it has an adjusting means capable of adjusting the rotation restricting position of the second operating arm.

(Operation) By adjusting the rotation restricting position of the second operating arm, the lift amount of the presser foot is adjusted. Therefore, by operating the second drive mechanism until the rotation of the second actuating arm is regulated, the rise of the cloth presser rises by the adjusted rise amount, so that the rise of the cloth presser is accurately adjusted every time. It rises with the amount of rise.

(Embodiment) An embodiment of the present invention will be described below with reference to the accompanying drawings.

As shown in the figure, the presser bar 2 is attached to the sewing machine frame 1.
Is held via a bearing 3 so as to be vertically movable, and the presser bar 2 is constantly urged downward in the figure by the urging force of a spring 4 arranged between the upper end of the presser bar 2 and the sewing machine frame 1. ing. A cloth presser 5 is fixed to the lower part of the presser bar 2, and a presser clamp 6 is fixed to the upper part. A first bell crank 7 and a second bell crank 8 are rotatably supported on the sewing machine frame 1 by pins 9 and 10, respectively. One end of the first bell crank 7 is engaged with the lower surface of the presser body 6,
The other end is connected to the other end of the second bell crank 8 via a rod 11. A pivot 13 is rotatably supported by a bearing 12 on an oil pan (not shown) arranged at the bottom of the sewing machine frame 1. A bell-crank-shaped first operating arm 14 is fixed to the pivot 13 so as to rotate integrally with the pivot 13.
One end of the first operating arm 14 is linked to the other end of the second bell crank 8 via a rod 15 connected to the other end of the second bell crank 8 and a push-up rod 16 supported by an oil pan so as to be vertically movable. Has been done. The other end of the first operating arm 14 is fixed via a rod 17 and a link 18 to a sewing machine table (not shown) arranged at the bottom of the sewing machine frame 1 by operating a foot pedal switch (not shown). An operating rotary solenoid 19 is connected. A second actuating arm 20 is pivotally supported on the pivot 13 via the pivot 13 so as to be relatively rotatable. A knee raising lever 21 is connected to the second operating arm 20, and a knee rest 22 is fixed to the tip of the knee raising lever 21.
An L-shaped stopper 23 is fixed to the sewing machine table, and the knee raising lever 21 is constantly urged clockwise in the drawing by the urging force of a spring 24 arranged between the knee raising lever 21 and the stopper 23. Abut with 23 Knee lift lever 21
Is held in the initial position. A collar 25 is fixed to the pivot 13 so as to rotate integrally with the pivot 13. The collar 25 is provided with a first projecting pin 26 extending in a direction perpendicular to the pivot 13, and the first projecting pin 26 is provided on the knee raising lever 25.
Of the second actuating arm 20 in the counterclockwise direction shown in the drawing against the urging force of the spring 24 of the first working arm 20 extending in a direction parallel to the pivot 13 provided on the second working arm 20. It is adapted to engage with the two protruding pins 27. 2nd working arm
An adjusting screw 28 is screwed through the 20. This adjustment screw
The tip end of 28 is capable of contacting the stopper 23, and the contact between the stopper 23 and the tip of the adjusting screw 28 causes the second operating arm to contact.
The rotation of 20 is restricted.

 Next, the operation will be described.

In the figure, when the rotary solenoid 19 is operated by operating the foot pedal switch, the first operating arm 14 rotates together with the pivot 13 in the counterclockwise direction in the figure via the link 18 and the rod 17. At this time, the rotation of the pivot 13 causes the first protruding pin 26 to rotate.
Since the rotation is in the direction in which the and the second protruding pin 27 are separated from each other,
The second operating arm 20, that is, the knee raising lever 21 does not operate. The rotation of the first operating arm 14 causes the second bell crank 8 to rotate clockwise in the drawing via the push-up rod 16 and the rod 15, and the rotation of the second bell crank 8 causes the first bell crank 8 to rotate through the rod 11. The bell crank 7 rotates clockwise in the drawing. As a result, due to the engagement between the one end of the first bell crank 7 and the lower surface of the presser body 6, the presser bar 2, that is, the cloth presser 5 is lifted upward in the figure against the biasing force of the spring 4.

In addition, in the figure, the knee raising lever 22 is operated by operating the knee rest 22.
When 21 is rotated counterclockwise in the drawing against the urging force of the spring 24, the second operating arm 20 rotates until the tip end of the adjusting screw 28 and the stopper 23 come into contact, that is, the second operating arm 20 rotates. Rotate until is regulated. By the rotation of the second operating arm 20, the first and second projecting pins 26 and 27 are engaged with each other to pivot the shaft.
13 and the first operating arm 14 rotate clockwise in the drawing. The rotation of the first operating arm 14 causes the second bell crank 8 to rotate clockwise in the drawing via the push-up rod 16 and the rod 15, and the rotation of the second bell crank 8 causes the first bell crank 8 to rotate through the rod 11.
The bell crank 7 rotates clockwise in the drawing. As a result, due to the engagement between the one end of the first bell crank 7 and the lower surface of the presser body 6, the presser bar 2, that is, the cloth presser 5 is lifted upward in the figure against the biasing force of the spring 4.

During the lifting operation of the work clamp 5 by the operation of the knee rest 22, the adjusting screw 28 is operated to bring the stopper 23 into contact with the tip of the adjusting screw 28, that is, the rotation restricting position of the second operating arm 20. By operating the knee pad 22 at the time of sewing small curved lines by adjusting the amount of rise of the presser foot 5 which is determined by the thickness of the cloth to be sewn (not shown), the number of layers of cloth, etc. Thus, the work clamp 5 can be slightly lifted to perform the sewing direction changing work, and it is possible to prevent the occurrence of a sewing wrinkle, a sewing jam or the like during the sewing direction changing work.

As described above, since the lift amount of the presser foot 5 is adjusted by adjusting the rotation restricting position of the second operating arm 20, the knee rest 22 is simply restricted from rotating. By operating up to, the rise of the cloth presser 5 is raised by the adjusted rise amount, and the operation is easy, and the rise of the cloth presser 5 can be raised accurately by the adjusted rise amount every time.

[Effect of device]

The present invention includes a rotatable pivot and a first pivot fixed to the pivot.
A first operating arm which is rotated by the operation of the drive mechanism; and a presser bar having a cloth presser fixed to a lower portion which is linked to the first operating arm through a linking mechanism and is vertically moved by the rotation of the first operating arm. ,
A second actuating arm pivotally supported by the pivot and rotated by actuation of a second drive mechanism, and the pivot and the second actuating arm disposed between the pivot and the second actuating arm when the first mechanism is actuated. Two
In a presser foot lifting device for a sewing machine, which has a linking means for rotating the operating arm relative to each other and integrally rotating the pivot shaft and the second operating arm when the second drive mechanism is operating, the sewing machine is provided on the second operating arm. The presser foot lifting device of the sewing machine is configured to have the adjusting means capable of contacting the stopper and restricting the rotation of the second operation arm and adjusting the rotation restriction position of the second operation arm. By operating the drive mechanism until the rotation of the second actuating arm is restricted, the rise of the work clamp is increased by the adjusted rise amount, and the rise of the work clamp is accurately raised by the adjusted rise amount every time. Can be made.

[Brief description of drawings]

FIG. 1 is a perspective view of a presser foot lifting device according to the present invention. 2 …… Presser bar, 5 …… Cloth clamp, 7 …… First bell crank (coupling mechanism), 8 …… Second bell crank (coupling mechanism), 13 ……
Axis, 14 …… First operating arm, 19 …… Rotary solenoid (first drive mechanism), 20 …… Second operating arm, 21 …… Knee lift lever (second drive mechanism), 22 …… Knee rest (first 2 drive mechanism), 23
...... Stopper, 26 ...... First protruding pin (coupling means), 27 ......
2nd protruding pin (coupling means), 28 ... Adjusting screw (adjusting means).

Claims (1)

[Scope of utility model registration request] 1. A rotatable pivot shaft and a first shaft fixed to the pivot shaft.
A first operating arm which is rotated by the operation of the drive mechanism; and a presser bar having a cloth presser fixed to a lower portion which is linked to the first operating arm through a linking mechanism and is vertically moved by the rotation of the first operating arm. ,
A second actuating arm pivotally supported by the pivot and rotated by actuation of a second drive mechanism, and the pivot and the second actuating arm disposed between the pivot and the second actuating arm when the first mechanism is actuated. Two
In a presser foot lifting device for a sewing machine, which has a linking means for rotating the operating arm relative to each other and integrally rotating the pivot shaft and the second operating arm when the second drive mechanism is operating, the sewing machine is provided on the second operating arm. A presser foot lifting device for a sewing machine, which has an adjusting means capable of contacting a stopper and restricting the rotation of the second operation arm and adjusting the rotation restriction position of the second operation arm.