Sewing machine provided with a threading device and a needle bar raising device
AssigneeBrother Kogyo Kabushiki Kaisha
InventorMasao Ogawa
Life of this patent
Estimating the term…
Abstract
A sewing machine comprising a threading device and a needle-bar raising means. A threading switch is operated and a sewing machine motor is stopped. Subsequently, thread is passed onto a linkage, a needle bar is disconnected from an arm shaft, and the needle bar is raised to a given position. After the needle bar is set in its uppermost position, thread stretched out from the linkage 38 to the front of an eye in a needle is passed through the eye in the needle. If the end of thread is manually held in front of the eye in the needle to stretch out prior to threading operation, the needle bar does not lower, thus enhancing operational safety and preventing thread from loosening.
Claims21
A raising and threading apparatus for raising a needle bar and threading a needle of a sewing machine, wherein the needle bar is movably mounted on a frame of the sewing machine, the needle is attached to one end of the needle bar, and the sewing machine further comprises a sewing transmission driven by a main drive means for moving the needle bar, the raising and threading apparatus comprising:
- needle-bar raising means for raising the needle bar to a preparatory position prior to a threading operation;
- threading means for threading the needle when the needle bar is raised to the preparatory position;
- reversible drive means operatively connected to the threading means for moving the threading means toward and away from the needle;
- detecting means for detecting a position of the threading means;
- and
- control means for controlling a drive direction of the reversible drive means;
- wherein
- the needle-bar raising means raises the needle bar to the preparatory position independently from the rotation of the main drive means and sewing transmission during a sewing operation.
A raising and threading apparatus for raising a needle bar and threading a needle of a sewing machine, wherein the needle bar is movably mounted on a frame of the sewing machine, the needle is attached to one end of the needle bar, and the sewing machine further comprises a sewing transmission driven by a main drive means for moving the needle bar, the raising and threading apparatus comprising:
- needle-bar raising means for raising the needle bar to a preparatory position prior to a threading operation;
- a threading rod mounted such that the threading rod is movable relative to the needle bar along and rotatable about a threading rod axis parallel to a needle bar axis;
- and
- 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 and the needle bar is raised to the preparatory position, the threading means comprising threading hook extending means attached to a first end of the threading rod for extending a threading hook when the needle bar rotates about the needle bar axis, and an actuating cylinder mounted on a second end of the threading rod for rotating the needle bar about the needle bar axis when the needle bar is in the preparatory position, wherein
- the needle-bar raising means raises the needle bar to the preparatory position independently from the rotation of the main drive means and sewing transmission during a sewing operation.
A raising and threading apparatus for raising a needle bar and threading a needle of a sewing machine, wherein the needle bar is movably mounted on a frame of the sewing machine, the needle is attached to one end of the needle bar, and the sewing machine further comprises a sewing transmission driven by a main drive means for moving the needle bar, the raising and threading apparatus comprising:
- clutch means for disconnecting the sewing transmission from the needle bar prior to the threading operation;
- a resilient retracting member attached between the frame and the needle bar for exerting a force on the needle bar away from the needle to retract the needle bar into the preparatory position when the clutch means disconnects the sewing transmission from the needle bar;
- a threading rod mounted such that the threading rod is movable relative to the needle bar along and rotatable about a threading rod axis parallel to a needle bar axis;
- and
- 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 and the needle bar is raised to the preparatory position;
- wherein the clutch means comprises a needle bar connecting stud connecting to the sewing machine transmission and slidably mounted on the needle bar such that the needle bar connecting stud is movable in either direction along an axis of the needle bar,
- clutch latch means rotatably 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, and
- actuating means for rotating the clutch latch means to detach the needle bar connecting stud from the needle bar, the actuating means comprising disconnecting means for disengaging the clutch latch 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 the threading rod, along a line parallel to the needle bar, such that when the drive means moves the drive board along the threading rod towards the needle, the drive board contacts the disconnecting means and causes the disconnecting means to rotate in the disconnecting direction.
Dependencies are inferred from the claim text.