公开(公告)号：US10961645B2

公开(公告)日：2021-03-30

申请号：US16409117

申请日：2019-05-10

Applicant: L&P Property Management Company

Inventor： Steven Marcangelo

IPC: D05B29/02 ,  D05C9/20

Abstract: A sewing machine comprises a crank shaft, a first drive shaft, a second drive shaft, a needle assembly, a presser foot, and an upper walking foot. A first crank arm assembly is connected to the crank shaft to the first drive shaft. A first linkage assembly is connected to the first drive shaft to the needle assembly. A second crank arm assembly is connected to the first drive shaft to the second drive shaft. A second linkage assembly is connected to the second drive shaft to the presser foot and the upper walking foot. The second linkage assembly is configured to cause out-of-phase reciprocatory movement of the presser foot and the upper walking foot. The second crank arm assembly has a variable length that is selectably adjustable by an operator to yield at least first and second different stepping heights of the upper walking foot.