JPH058953Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an inner hook for a half-rotation sewing machine.

[Conventional technology]

Conventionally, in the case of an inner hook, a narrow groove is cut at the boundary between the sliding collar and the bulge for enclosing the bobbin case for processing purposes and to collect oil and dust. It ends just before the tip for catching the upper thread loop, but at the other end, this narrow groove extends all the way to the end.

[Problems that this invention attempts to solve]

The loop of the upper thread is captured by the tip of the needle and the hook is rotated almost 180°.
When the loop rotates, it passes through the sliding flange end, but at this time, the recess formed by the aforementioned thin groove and the sliding flange end allows it to pass smoothly, which is the cause of thread breakage. It is considered one.

[Means to solve the problem]

In conventional inner pots, the narrow groove is cut out at the boundary between the sliding flange and the bulge on both the front and back sides, and a recess is formed on this end surface. In this case, these two narrow grooves were not cut all the way to the end, but the end surface of the stopper sliding collar was made to have a smooth shape before the end, so that the needle thread loop could pass smoothly.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. Figures 1 to 3 show conventional inner pots.
The figure is a front view, FIG. 2 is a side view, and FIG. 3 is a rear view. As shown in the figure, the sliding flange 2 of the inner pot 1 and the large pot
Narrow grooves 5a and 5 are formed at the boundaries between the bulges 4a and 4b of the bobbin case enclosing part 3 for machining purposes and for dust collection.
b has been deleted. As shown in FIGS. 1 and 3, one of these 5a and 5b disappears before the needle thread loop catching tip 6, and the other extends up to the end 7 of the sliding collar 2. For this reason, the end 7 of the sliding collar has a recess 8 due to the narrow grooves 5a and 5b, as is clear in FIG.
a and 8b will be formed. Since this concave portion causes thread breakage, it would be better to eliminate this concave portion. Therefore, in the present invention, as shown in FIGS. 4 and 6, the narrow grooves 5a and 5b are not cut all the way to the end of the sliding collar, but end just before that end. As a result, the end of the sliding collar is free of recesses as shown in FIG.

[Effect of idea]

As a result of the above-mentioned improvements, there is no occurrence of thread breakage, particularly in extreme sewing operations such as high-speed rotation or when using extremely thick or extremely thin threads.

[Brief explanation of the drawing]

Figures 1 to 3 are drawings of a conventional inner pot, with Figure 1 being a front view, Figure 2 being a side view, and Figure 3 being a rear view. 4 to 6 are partial drawings of the inner pot according to the present invention, in which FIG. 4 is a front view, FIG. 5 is a side view, and FIG. 6 is a rear view. 1... Inner pot, 2... Sliding collar, 5a, 5b... Thin groove, 8a, 8b... Recessed portion formed in the sliding collar end surface.

Claims (1)

[Scope of utility model registration request] The inner hook of the sewing machine has narrow grooves 5a and 5b cut at the boundary between the sliding collar 2 and the bulges 4a and 4b forming the bobbin case enclosing section 3, and a tip that catches the upper thread loop in the sliding collar. An inner pot characterized by having a narrow groove stopped in front of the end face on the opposite side of the pot.