ES270562A1 - Improvements in sewing machines (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Improvements in sewing machines, comprising a frame (1) carrying, in its upper part, a drive shaft (2) of a crank (3) that drives a rod-needle (4) which slides vertically in a cradle (8) capable of oscillating; a "triangular" cam (21) driven from said shaft (2) and which can actuate in oscillation movement a first slide (16) along which the end (15) of a connecting rod (14) can be moved whose other end is articulated to the mentioned cradle (8), to govern transverse movements of the needle-bar (4); the displacements of said connecting rod end (15) along the first slide (16) can be governed from a modulation cam (47) of the amplitude of said transverse movements, which modulation cam ( 47) is dragged from said shaft (2) and is in contact with a feeler (46) forming the end of a lever (27) whose other end (26) is articulated to an articulated arm (25) of another part, to said connecting rod (14); the articulation point (17) of said first slide (16) is supported by an arm (18), articulated in turn to the frame (1) and whose angular position is capable of being governed from a centering member by hand (76) by means of transmission organs (82-88) to vary the contraction position of the needle-bar (4), a machine characterized by the fact that it comprises a mechanism comprising a single selection maneuvering organ ( 37), integral with a control shaft (36) which carries working distribution cams (38, 39, 40, 41 and 42) angularly fixed thereon and intended to be established or suppressed, by rotation of the single selecting maneuvering member ( 37), the combined or isolated action of the manually contracted member (76) of the needle bar (4) of said "triangular" cam (21), of said modulation cam (47) and of a first cam of control (59) solidaria of this one, destined to operate a palpador (60) of a second slide (61) articulated on the frame (1), allowing various points of support to a feeler finger (63) integral with a bar (64) articulated to the arm (18) that carries the point of articulation (17) of the first slide (16), at a point (65) of the same radius, so that the movements printed on said probe finger (63) can be transmitted directly to said cradle (8) of the needle bar (4) by said cam of control (59), while a spring (71) keeps the bar (64) supported against a first cam (38) of the distribution cams (38-42) integral with the single selection maneuvering member (37), while the profile of said cam (38) determines the position of the feeler finger (63) along the second slide (61). (Machine-translation by Google Translate, not legally binding)