A feeding device of an industrial sewing machine comprises a shell base, a main connecting rack having a first bar portion and a second bar portion, a terminal driven rack mounted at the first bar portion and the second bar portion, a first driven rack, a raising-driven mechanism and a driving shaft. The first driven rack is mounted at the first bar portion and connected to the shell base, and has a first sliding recess. The raising-driven mechanism has a second driven rack mounted at the second bar portion and having a second sliding recess. A raising-connecting rod is mounted at the second driven rack and the terminal driven rack. The driving shaft has a first crank mounted through the first sliding recess and a second crank mounted through the second sliding recess. The feeding device has a compact volume to facilitate ease in maintenance.

A sewing machine, in which a presser foot and a throat plate are detachable, includes a feed dog bracket, a feeding dog and a mounting portion. The feed dog bracket is driven according to a transfer direction of a fabric. The feeding dog transfers the fabric on the throat plate. The mounting portion detachably mounts the feeding dog on the feed dog bracket. The feeding dog includes a cam portion which is mounted on the mounting portion. The cam portion includes first, second and third cam surfaces. The first cam surface has a surface-contact with a first receiving surface of the mounting portion. The second cam surface has a line-contact with an end portion of a second receiving surface of the mounting portion. The third cam surface is pressed by a pressing member of the mounting portion.

A sewing machine, in which a presser foot and a throat plate are detachable, includes a feed dog bracket, a feeding dog and a mounting portion. The feed dog bracket is driven according to a transfer direction of a fabric. The feeding dog transfers the fabric on the throat plate. The mounting portion detachably mounts the feeding dog on the feed dog bracket. The feeding dog includes a cam portion which is mounted on the mounting portion. The cam portion includes first, second and third cam surfaces. The first cam surface has a surface-contact with a first receiving surface of the mounting portion. The second cam surface has a line-contact with an end portion of a second receiving surface of the mounting portion. The third cam surface is pressed by a pressing member of the mounting portion.

Provided is a sewing machine including: a pair of feed bars that are incorporated in a cylinder and are each capable of conveying a material by moving to draw elliptical trajectories in side view; an oil seal abutting outer surfaces of the pair of feed bars by surrounding an entire periphery in a direction intersecting a longitudinal direction of the pair of feed bars; and a seal-supporting unit provided on an inner wall of the cylinder and configured to support the oil seal, wherein the pair of feed bars are configured to be movable upward through the opening of the cylinder, the seal-supporting unit includes an upper opening that allows the pair of feed bars to move upward, and the seal-supporting unit is immovable relative to the cylinder when the pair of feed bars move upward through the opening.

Provided is a sewing machine including: a pair of feed bars that are incorporated in a cylinder and are each capable of conveying a material by moving to draw elliptical trajectories in side view; an oil seal abutting outer surfaces of the pair of feed bars by surrounding an entire periphery in a direction intersecting a longitudinal direction of the pair of feed bars; and a seal-supporting unit provided on an inner wall of the cylinder and configured to support the oil seal, wherein the pair of feed bars are configured to be movable upward through the opening of the cylinder, the seal-supporting unit includes an upper opening that allows the pair of feed bars to move upward, and the seal-supporting unit is immovable relative to the cylinder when the pair of feed bars move upward through the opening.

A feeding device of an industrial sewing machine comprises a shell base, a main connecting rack having a first bar portion and a second bar portion, a terminal driven rack mounted at the first bar portion and the second bar portion, a first driven rack, a raising-driven mechanism and a driving shaft. The first driven rack is mounted at the first bar portion and connected to the shell base, and has a first sliding recess. The raising-driven mechanism has a second driven rack mounted at the second bar portion and having a second sliding recess. A raising-connecting rod is mounted at the second driven rack and the terminal driven rack. The driving shaft has a first crank mounted through the first sliding recess and a second crank mounted through the second sliding recess. The feeding device has a compact volume to facilitate ease in maintenance.

A feeding device of an industrial sewing machine comprises a shell base, a main connecting rack having a first bar portion and a second bar portion, a terminal driven rack mounted at the first bar portion and the second bar portion, a first driven rack, a raising-driven mechanism and a driving shaft. The first driven rack is mounted at the first bar portion and connected to the shell base, and has a first sliding recess. The raising-driven mechanism has a second driven rack mounted at the second bar portion and having a second sliding recess. A raising-connecting rod is mounted at the second driven rack and the terminal driven rack. The driving shaft has a first crank mounted through the first sliding recess and a second crank mounted through the second sliding recess. The feeding device has a compact volume to facilitate ease in maintenance.

A sewing machine having a device for manually changing a feed dog (10), including the feed dog (10) and a feed-dog holder (30). The feed-dog holder (30) is disposed in an arm bed (103) that is associated with the sewing machine, and the feed dog (10) is receivable in a clearance (31, 81) of the feed-dog holder (30). The feed dog (10) that is located in the clearance (31, 81) has a support face (15) which may be disposed parallel with the surface of a sewn-product support which may contain a needle-hole plate (113) or be configured as a needle-hole plate (113), the sewn-product support and/or the needle-hole plate (113) may at least partially be formed by the surface of the arm bed (103), and the support face (15) may be received in an opening (140) of the needle-hole plate (113). The feed dog (10) is fastenable in the clearance by a fastening element (40, 82, 83) or of a setting element (50) such that the support face (15) is alignable so as to be substantially parallel with the surface of the sewn-product support or of the needle-hole plate (113). The fastening element (40, 82, 83) or the setting element (50) is releasably held in the feed-dog holder (30).

A sewing machine having a device for manually changing a feed dog (10), including the feed dog (10) and a feed-dog holder (30). The feed-dog holder (30) is disposed in an arm bed (103) that is associated with the sewing machine, and the feed dog (10) is receivable in a clearance (31, 81) of the feed-dog holder (30). The feed dog (10) that is located in the clearance (31, 81) has a support face (15) which may be disposed parallel with the surface of a sewn-product support which may contain a needle-hole plate (113) or be configured as a needle-hole plate (113), the sewn-product support and/or the needle-hole plate (113) may at least partially be formed by the surface of the arm bed (103), and the support face (15) may be received in an opening (140) of the needle-hole plate (113). The feed dog (10) is fastenable in the clearance by a fastening element (40, 82, 83) or of a setting element (50) such that the support face (15) is alignable so as to be substantially parallel with the surface of the sewn-product support or of the needle-hole plate (113). The fastening element (40, 82, 83) or the setting element (50) is releasably held in the feed-dog holder (30).

A sewing machine capable of replacing a feed dog in accordance with a type of sewing, the sewing machine including a feed bar performing a horizontal motion and a vertical motion by interlocking with a feeding mechanism, a feed dog detachably mounted on the feed bar, and a control unit that identifies the feed dog mounted on the feed bar. In the sewing machine, the feed dog includes an identification member that corresponds to a type of the feed dog, the feed bar includes a sensor that detects the identification member and outputs an identification signal, and the control unit includes a feed dog identifying means that, based on the identification signal from the sensor member, identifies the type of the feed dog mounted on the feed bar.