| 摘要 |
An electro-pneumatically controlled mechanism is provided, for instance for use with a sewing machine having a rectilinear feed means, to enable the curved and/or straight marginal portions of flexible sheet-like material to be automatically fed and processed continuously through the operating zone of a tool (such as a needle) of the machine. To aid in attaining bias of an edge of the work against an edge gage a work supporting table has an at least partly arcuate periphery over which the work may be draped. A corner sensing means actuates a mechanism for gripping a portion of the work at the proper time and swinging it approximately about a turning center thereby progressively positioning the work relative to the tool. In an illustrative over-edging machine, which is provided with conventional trimming means, a rectangular work piece thus progressively has its successive corners trimmed to a predetermined radius and sewn. A second sensor counts the successive corners turned in order to automatically stop operations when all or a desired portion of a periphery has been processed. A third sensor automatically serves to check pressure of the engagement of a work edge with the edge gage to prevent unwanted buckling or folding of the work edge. |
