Patent GB-190320550-A (GB)
Title: Improvements in Buttonhole Sewing Machines.
Inventor: BROMHEAD SAMUEL SIDNEY
Filed: 1903-09-24
Granted: 1904-01-14
Abstract: 20,550. Bromhead, S. S., [Herrmann & Co., A.]. Sept. 24. Buttonhole-sewing machines.-Relates to buttonhole-sewing machines which work with one needle, and make buttonholes with eyes, and consists mainly in a device for forming radial stitches between the points 53, 54, Fig. 9, of the eye of the buttonhole. During the sewing of the whole buttonhole, with the exception of the part from 53 to 54, the needle vibrates laterally, but from 53 to 54 the needle is given an up-and-down motion only, while the cloth presser is caused to move to and fro in the direction of the length of the buttonhole. Fig. 1 shows an elevation of the machine, the parts being shown in the position they would occupy at the beginning of the sewing of a buttonhole. The cloth presser 7 is mounted on a shaft 8, the movements of which are controlled by a guiding-frame 6 which can move about two axes 32, 37 at right-angles to each other. The frame 6 is linked, as shown, to a rod 5. The rod 5 is always kept in contact with a roller 10 fixed to the frame t of the machine, and receives two simultaneous motions : - (1) A reciprocating motion due to a lever r pivoted at s to the frame t, and operated through a lever p pivoted at o which carries a roller n adapted to engage a heart-shaped cam m, Fig. 6, formed in the upper face of a disc c, driven, by means of a ratchet-wheel d and a pawlf, from the main shaft k through a cam l, pivoted lever h, and a draw-bar g. (2) A motion of oscillation about the roller 10 by means of a lever 34 pivoted at 33 to the frame t, and operated by means of a roller 36 which engages the upper edge of the disc c. The upper end of the lever 34 is forked, and carries two rollers 35 which bear one on either side of the rod 5. By means of the two motions described, the cloth-presser and fabric are brought under the action of the needle for the whole of the buttonhole except the part of the eye from 53 to 54. When this portion of the eye is to be sewn, a bolt 1 which connects the lever r to the bars 5 is pushed down against the action of a spring z by means of a finger 29 on a lever 26, and so renders the lever r inactive. The lever 26 is operated by a rod 17 pivoted at 18 to a pivoted lever 19 ; a fork 20 on the end of the lever 19 engages a pin 20 on a slotted swinging link 22 pivoted at 23. The link 22 receives its swinging movement from the main shaft through the cam l, lever h, a link 28, a lever 25, and the lever 26 which is pivoted to the link 22 at 27. A sloping recess 31 formed in the lower end of the link 22 engages an arm 30 on the bar 5 and so transmits the necessary to-and-fro movement to the cloth-presser to form radial stitches. The sloping form of the recess 31 as it is raised or lowered by the lever 17 causes a longitudinal displacement of the bar 5 between the points 53, 62 and 62, 54, Fig. 9. The lever 17 is operated by means of a roller 12 which engages with a groove 11 formed in the side of the disc c. When the portion 53 to 54 of the eye has been completed, the cam 29 releases the bolt 1 which is caused to re-engage with the bar 5 by means of the spring z, and the buttonhole is completed as described above. Needle-driving; needle-bars, vibrating laterally.- The up-and-down motion of the needle shaft 38, Fig. 4, is caused by a disc 39 and connecting-rod 40. The needle-bar is mounted in a frame 41 pivoted at 42. A slotted portion 45 of the frame is pivoted at 48, and receives a swinging motion from a cam 49 on the spindle k. The swinging motion is transmitted to the frame 41 and needle shaft through a lever 44 pivoted to the frame at 3, 4 and connected to the slot 45 by a roller 46. The amount of the lateral motion of the needle depends upon the position of the roller in the slot 45. When the lever 17, Fig. 1, pulls down the end 20 of the lever 19 so as to disengage the bolt 1 from the bar 5, the other end of the lever 19 pushes the roller 46 to the top of the slot in line with both pivots 48, 43. In this position, the roller 46 and lever 44 are not affected by the swinging of the slot 45, and the needle moves up and down only. When the roller is in its lowest position in the slot, the needle receives its maximum swinging motion to form the barring of the buttonhole.