JPH03128076U

JPH03128076U -

Info

Publication number: JPH03128076U
Application number: JP3456890U
Authority: JP
Priority date: 1990-03-31
Filing date: 1990-03-31
Publication date: 1991-12-24
Anticipated expiration: 2005-03-31
Also published as: JPH0873Y2

Description

[Brief explanation of drawings]

第１図ａ〜ｅはこの考案の一実施例の構成及び
動作過程を示す底面図、第２図ａ〜ｅは従来のミ
シンの糸切り装置を示す底面図、第３図ａ，ｂは
第２図に示したものにおける第１の切断刃の往動
状態を示す一部縦断側面図、第４図は千鳥縫いミ
シンに糸切り装置を適用する場合の第２の切断刃
の最往動位置を示す説明側面図である。１……ミシン針板、３……第２の切断刃、３ａ
……長溝、３ｄ_１……第１の係合凹部、３ｄ_２…
…第２の係合凹部、４……第１の切断刃、４ｄ_１……第１の解除部、４ｄ_２……第２の解除部、５
……嵌合突起、６……係止体、Ｋ……ミシン釜、
Ｉ１……上糸ループ、Ｉ１_１……針側ループ糸、
Ｉ１_２……布側ループ糸、Ｉ……下糸。 Figures 1 a to e are bottom views showing the configuration and operating process of an embodiment of this invention, Figures 2 a to e are bottom views showing a conventional sewing machine thread trimming device, and Figures 3 a and b are bottom views showing the construction and operation process of an embodiment of this invention. A partially longitudinal side view showing the forward movement state of the first cutting blade in the one shown in Figure 2, and Figure 4 shows the most forward movement position of the second cutting blade when the thread trimming device is applied to a zigzag stitch sewing machine. It is an explanatory side view showing. 1...Sewing machine throat plate, 3...Second cutting blade, 3a
... Long groove, 3d ₁ ... First engagement recess, 3d ₂ ...
...Second engagement recess, 4...First cutting blade, 4d ₁ ...First release part, 4d ₂ ...Second release part, 5
... Fitting projection, 6 ... Locking body, K ... Sewing machine hook,
I1...Needle thread loop, I1 ₁ ...Needle side loop thread,
I1 ₂ ...Fabric side loop thread, I...Bobbin thread.

Claims

[Scope of Claim for Utility Model Registration] A drive means that is disposed between the sewing machine throat plate and the sewing machine hook and that operates in response to a thread trimming command moves the sewing needle from an initial position laterally away from the dropping position to a horizontal position. a first cutting blade that cuts and captures the needle-side loop thread and bobbin thread in the needle thread loop through reciprocating motion; a fitting projection protruding from one surface of the first cutting blade; and the first cutting blade. The first cutting blade is overlapped with the first cutting blade, is held so as to be able to reciprocate in the same direction as the first cutting blade, and has a long groove into which the fitting protrusion is fitted. a second cutting blade formed to have a length of; first and second engagement recesses formed on one side of the second cutting blade at a predetermined interval from each other; The second cutting blade is urged to come into pressure contact with one side of the blade, and when the second cutting blade moves forward to a predetermined position, it fits into the first recess to prevent the first cutting blade from moving forward. , a locking body that fits into the second engagement recess to prevent forward movement of the second cutting blade when the second cutting blade moves forward to a predetermined position; a first release part that presses the locking body in a direction away from the second cutting blade during the forward movement process of the first cutting blade to release the engagement between the locking body and the first engagement recess; , a second release portion that presses the locking body in a direction away from the second cutting blade during the forward movement of the first cutting blade to release the engagement between the locking body and the second engagement recess; A thread cutting device for a sewing machine, characterized in that: is formed on a side surface of the first cutting blade.