Stitching mechanism

Claim 2

A stitching mechanism mountable on the bed of an ordinary sewing machine, including a base plate provided with a window, said base plate being mountable on said bed, plural pulleys mounted rotatably on said base plate at positions surrounding said window, a first endless string stringed doubly on said pulleys, a first supporting rod connected at right angles to the unidirectionally moving portion of said first endless string, a second supporting rod connected at right angles to the oppositely moving portion of said first endless string, a stitch frame mounted slideably on said first supporting rod, said stitch frame being provided with a slot perpendicular to said first supporting rod, a pair of pulleys mounted rotatably on said second supporting rod, a second endless string stringed doubly on said pulleys on the second supporting rod, an arm connected to the unidirectionally moving portion of said second endless string, the free end of said arm being inserted slideably in said slot and a tracing member with a tracing pen holder and bearing portions, the second supporting rod being inserted in said bearing portions whereby said tracing member can slide along said second supporting rod.

Claim 3

A stitching mechanism as described in claim 1 including a transparent cover fit detachably to said base plate.

Claim 4

A stitching mechanism as described in claim 1, including a pair of guiding plate secured on said base plate near both ends of said first and second supporting rods whereby the longitudinal movement of said rods can be prevented.

Claim 5

A stitching mechanism mountable on the bed of an ordinary sewing machine, including a base plate provided with a window, said base plate being mountable on said bed, plural pulleys mounted rotatably on said base plate at positions surrounding said window, a first endless string stringed doubly on said pulleys, a first supporting rod connected at right angles to the unidirectionally moving portion of said first endless string, a pair of grooved rollers attached to both ends of said first supporting rod, a pair of guiding plates disposed on the opposite side portions of said base plate, said grooved rollers being put rollably on said guiding plates, a stitch frame mounted slideably on said first supporting rod, said stitch frame being provided with a slot perpendicular to said first supporting rod, a tracing base provided with integral bearing portions and tracing slot formed longitudinally, said tracing base being connected at right angles to the oppositely moving portion of said first endless string whereby said tracing slot can be parallel to said first supporting rod, a second supporting rod provided with a Pair of grooved rollers at both ends, said grooved rollers being mounted slideably on said guiding plates, a pair of pulleys mounted rotatably on said tracing base, a second endless string stringed doubly on said pulleys of said tracing base in the direction parallel to said tracing slot, an arm base having a pair of bearing portions in which said second supporting rod being inserted for the slideable movement of said arm base, said arm base being connected to the unidirectionally moving portion of said second endless string, an arm secured on said arm base, the free end of said arm being fit slideably in said slot of said stitch frame and a tracing pen holder connected to the oppositely moving portion of said second endless string, said tracing pen holder being fit slideably in said tracing slot.

Claim 6

A stitching mechanism mountable on the bed of an ordinary sewing machine, including a base plate provided with a window, said base plate being mountable on said bed, plural pulleys mounted rotatably on said base plate at positions surrounding said window, a first endless string stringed doubly on said pulleys, a first supporting rod connected at right angles to the unidirectionally moving portion of said first endless string, a pair of grooved rollers attached to both ends of said first supporting rod, a pair of guiding plates disposed on the opposite side portions of said base plate, said grooved rollers being put rollably on said guiding plates, a stitch frame mounted slideably on said first supporting rod, said stitch frame being provided with a slot perpendicular to said first supporting rod, a tracing base provided with integral bearing portions and tracing slot formed longitudinally, said tracing base being connected at right angles to the oppositely moving portion of said first endless string whereby said tracing slot can be parallel to said first supporting rod, a second supporting rod provided with a Pair of grooved rollers at both ends, said grooved rollers being mounted slideably on said guiding plates, a pair of pulleys mounted rotatably on said tracing base, a second endless string stringed doubly on said pulleys of said tracing base in the direction parallel to said tracing slot, an arm base having a pair of bearing portions in which said second supporting rod being inserted for the slideable movement of said arm base, said arm base being connected to the unidirectionally moving portion of said second endless string, an arm secured on said arm base, the free end of said arm being fit slideably in said slot of said stitch frame and a tracing pen holder connected to the oppositely moving portion of said second endless string, said tracing pen holder being fit slideably in said tracing slot.

Claim 7

A stitching mechanism as described in claim 4 in which said base plate is provided with an elongated hole for positioning adjustably one of said fastening screws whereby the tension of said first endless string can be adjusted.

Claim 8

A stitching mechanism as described in claim 4, in which said base plate is provided with a cut at its one side for inserting one of said fastening screws.

Claim 9

A stitching mechanism as described in claim 4, including a transparent cover mounted detachably on said base plate.