Sewing machine needle bar, sew machine and sewing machine needle bar menbrane forming method

Abstract

The invention provides a sewing machine needle bar, a sew machine and a sewing machine needle bar menbrane forming method. The sewing machine needle bar (19) and sew machine provided by the invention can confirm position of a base line without decreasing durability of the needle bar (19) eliminated with lubricant under condition of no oil provided. A bearing component of a sewing machine frame supports the needle bar (19) which runs through the bearing component and can move back and forth along an axis direction. A needle bar drive mechanism drives the needle bar to move back and forth. In order to adjust action time and lower limit position of the needle bar (19), three base lines (22, 23, 24) are marked on periphery of the needle bar (19). A DLC membrane (25) is formed in the peripheral sliding face where the needle bar (19) is opposite to the bearing component and at the rear part near to the base lines (22, 23, 24). And a DLC membrane (25) is formed at the part except the part near to the base lines (22, 23, 24).

Description

technical field [0001] The invention relates to a sewing machine needle bar and a sewing machine. In particular, the present invention relates to a sewing machine needle bar in which a wear-resistant coating is formed on the outer peripheral sliding surface of the needle bar facing the bearing member except for the vicinity of the base line, a sewing machine, and a coating forming method for the sewing machine needle bar. Background technique [0002] Conventionally, a bearing member of a sewing machine frame supports a sewing machine needle bar that penetrates the bearing member and is capable of reciprocating axially (up and down). The needle bar drive mechanism drives the needle bar to move back and forth up and down. In order to adjust the action timing and the lower limit position of the needle bar, a plurality of baselines are marked on the outer peripheral surface of the needle bar. The baseline is formed as follows. First, a thin groove is formed on the outer peri...

AI Technical Summary

Problems solved by technology

As mentioned above, it is difficult to see the baseline as it is also black

As a result, this sewing machine has a problem that it is difficult to adjust the movement timing and the lower limit position of the needle bar.

On the contrary, when the DLC coating is not formed on the outer peripheral surface of the needle bar, the metallic luster color remains on the outer peripheral surface of the needle bar, so the base line is easy to see, but the durability of the needle bar under the condition of no lubrication is reduced

Images