Bearing mechanism and sewing machine

Abstract

A sewing machine (1) of the invention comprises a bearing mechanism (25) slidably supporting the periphery of a needle bar (11) reciprocating vertically via a needle bar bearing part (12a). The bearing mechanism (25) is provided with a grease storage recess part (12d) filled with grease (G) and formed on the internal surface (12c) of the needle bar bearing part (12a); lubricant trap grooves (12e,12f) formed at both upper / lower sides of the grease storage recess part (12d) formed on the internal surface (12c) of the needle bar bearing part (12a).

Description

(1) Technical field [0001] The present invention relates to a bearing mechanism in which the outer periphery of a sliding shaft is supported by a bearing member and lubricated using a lubricant such as grease, and a sewing machine provided with the bearing mechanism. (2) Background technology [0002] Conventionally, in a mechanism in which a cylindrical sliding bearing member slidably supports the outer periphery of a sliding shaft reciprocating in the axial direction in a mechanical drive system, in order to lubricate the sliding shaft and prevent seizing, etc., the sliding A lubricant such as grease is used between the shaft and the bearing. In particular, in industrial sewing machines and household sewing machines, grease is used as a lubricant used in the needle bar bearings that support the needle bar that moves up and down at high speed. [0003] As a bearing mechanism for such a sewing machine, for example, Japanese Patent Laid-Open No. 2002-45587 is known. In this...

AI Technical Summary

Problems solved by technology

[0004] However, in the above-mentioned structure, since a large number of annular grooves are formed on the outer peripheral portion of the needle bar, several annular grooves are exposed upward or downward from the needle bar bearing as the needle bar moves up and down.

In this way, once the annular groove filled with grease is exposed to the outside, the grease will be consumed due to evaporation, or the grease will deteriorate due to contact with outside air.

In this case, the lubricating performance will decrease prematurely due to the consumption and deterioration of the grease

[0005] In addition, the grease spreads from the annular groove to the needle bar and flows downward, and the grease adheres to the outer periphery of the needle bar. This grease may get on the hands of the sewing worker or on the processing cloth.

In addition, it is necessary to form a plurality of annular grooves with a small width on the outer peripheral surface of the thinner needle bar. Due to the poor workability, there is a disadvantage that the processing is quite troublesome.

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