US 5,003,899 A · Apparatus for disconnecting a needle bar and threading on a sewing machine

Abstract

In a device for disconnecting a needle bar from a needle-bar connecting stud on a sewing machine, a drive source drives a moving board. The moving board lowers a predetermined distance until a threading hook goes through an eye in a needle. A disconnecting member rotates a clutch click and disconnects the clutch click from a needle-bar connecting stud. The needle bar thus disengages from the needle-bar connecting stud. The moving board further lowers, an actuating rod lowers, the actuating rod in turn lowers a threading rod, the threading rod further rotates, and the threading hook goes through the eye. The needle is thus threaded. The disconnecting operation and the threading operation are carried out by using the drive source in common. Consequently, the device is simple in structure and compact in size. Since the needle bar only rises to disengage from the needle-bar connecting stud, no scratches are given on the fabric. The sewing machine can effectively execute pattern-sewing, basting and other operations.

Claims25

Dependent claims

A clutch for a sewing machine having a needle bar movably mounted on a frame of the sewing machine, a needle attached to one end of the needle bar, and a sewing transmission for moving the needle bar, the clutch comprising:

a needle bar connecting stud connected to the sewing transmission and slidably mounted on the needle bar such that the needle bar connecting stud may move in either direction along an axis of the needle bar;
click means attached to the needle bar for selectively attaching the needle bar connecting stud to or detaching the needle bar connecting stud from the needle bar;
disconnecting means for operating the click means to detach the needle bar connecting stud from the needle bar when the disconnecting means rotates in a disconnecting direction;
and
drive means for moving a drive board relative to the needle bar along a line parallel to the needle bar, where, when the drive means moves the drive board along the line towards the needle, the drive board contacts the disconnecting means and causes the disconnecting means to rotate in the disconnecting direction.

2 more elements

A clutch and threading apparatus for a sewing machine having a needle bar movably mounted on a frame of the sewing machine, a needle attached to one end of the needle bar, and a sewing transmission for moving the needle bar, the clutch and threading apparatus comprising:

a needle bar connecting stud connected to the sewing transmission and slidably mounted on the needle bar such that the needle bar connecting stud may move in either direction along an axis of the needle bar;
click means attached to the needle bar for selectively connecting the needle bar connecting stud to or disconnecting the needle bar connecting stud from the needle bar;
a threading rod mounted such that the threading rod is movable relative to the needle bar along a first axis parallel to the needle bar axis;
threading means mounted on the threading rod for threading the needle when a threading hook attached to the threading rod is in a threading position adjacent to the needle;
disconnecting means for operating the click means to disconnect the needle bar connecting stud from the needle bar when the disconnecting means rotates in a disconnecting direction about an axis parallel to the needle bar axis;
and
drive means for moving a drive board relative to the needle bar in a line parallel to the needle bar axis, wherein;
when the drive means moves the drive board towards the threading position, the drive board contacts the threading means to move the threading means and threading rod into the threading position;
and
when the drive means moves the drive board towards the threading position, the drive board contacts the disconnecting means to rotate the disconnecting means in the disconnecting direction.

7 more elements

a needle bar connecting stud having a groove formed thereon connected to the sewing transmission and slidably mounted on the needle bar such that the needle bar connecting stud may move in either direction along an axis of the needle bar;
click means attached to the needle bar for selectively connecting the needle bar connecting stud to or disconnecting the needle bar connecting stud from the needle bar, where the click means comprises a click rotatably attached to the needle bar such that the click engages the groove when the click means connects the needle bar connecting stud to the needle bar;
a threading rod mounted such that the threading rod is movable relative to the needle bar along a first axis parallel to the needle bar axis;
threading means mounted on the threading rod for threading the needle when a threading hook attached to the threading rod is in a threading position adjacent to the needle;
disconnecting means for operating the click means to disconnect the needle bar connecting stud from the needle bar when the disconnecting means rotates in a disconnecting direction about an axis parallel to the needle bar axis;
and
drive means for moving a drive board relative to the needle bar in a line parallel to the needle bar axis, where when the drive means moves the drive board towards the threading position, the drive board contacts the threading means to move the threading means and threading rod into the threading position and the disconnecting means to rotate the disconnecting means in the disconnecting direction;
stop means attached to the frame along the needle bar axis;
a resilient retracting member attached between the frame and the needle bar for exerting a force on the needle bar away from the needle;
and
actuator means for moving the needle bar from the clutch position to the top sewing position;
wherein
the needle bar is mounted on the frame such that the needle bar moves along the needle bar axis between a needle bar clutch position in which a distal end of the needle bar away from the needle contacts the stop means and a top sewing position in which the distal end is a predetermined clutch distance away from the stop means;
and
when the click means detaches the needle bar connecting stud from the needle bar, the retracting member forces the needle bar from the top sewing position to the clutch position.

12 more elements

Dependencies are inferred from the claim text.

Apparatus for disconnecting a needle bar and threading on a sewing machine

Life of this patent

Apparatus for disconnecting a needle bar and threading on a sewing machine

Life of this patent

Abstract

Claims25