GB351402A - A machine for threading and tying paper bags or the like together - Google Patents

Abstract

351,402. Threading and tying paper-bags &c. together. HARTMANN, C. W., Lyngby, Copenhagen. March 18, 1930, No. 8653. [Class 146 (i).] A machine for threading bundles of paper bags or the like together comprises mechanism for feeding and cutting off a length of thread which is drawn through the bundle of bags 47, the free ends being gathered together and tied into a simple knot. The devices are actuated from a shaft 20, Fig. 1. Jaws 36, Fig. 2, carried by an arm 35 oscillated from the shaft 20 are opened by mechanism 38 engaging a fixed stop 62a, to grip the free end of the thread which passes from a bobbin 24 over a tensioning device 25 between spring-pressed members 26 forced rearwardly by the jaws during their movement towards the gripping position. The thread is drawn over an arc-shaped guide 39 concentric with the orbit of the jaws 36. The bags 47 are placed on a table 15 and clamped by a spring-pressed foot 21. A needle 17, Fig. 1, passing through perforations 16 in the table 15 and foot 21 pierces the bags and continues its upward movement until it passes through a hole in the guide 39 and engages the thread. During the downward movement of the needle it draws the thread in the form of a loop through the bags, the jaws 36 at the same time moving towards the members 26. Spring-pressed jaws frictionally engage the thread so as to prevent it slipping through the needle due to unequal tension on the two ends. Scissors 29 are now operated to cut off the length of thread. Subsequently the jaws 36 are operated by a member 62 engaging the mechanism 38 to release the thread. Knotting.-Before the needle 17 begins its upward movement, two jaw members 43, 46, Figs, 1 and 3, provided with holes to receive the needle 17 and mounted on a reciprocating carriage 41 are moved into engagement with the bags, the lower jaw 46 being received in a recess in the table 15 and the upper jaw 43 being opened by a cam 45 so as to lie in a recess in the foot 21 and above the bags. After the thread has been drawn through the bags, the jaws 43, 46 are moved away from the bags to draw the free ends of the thread together. In order to prevent the jaws 43, 46 pulling the thread out unequally, a spring-pressed stop 63 held inoperative by the jaw 46 snaps through the hole in the table 15 when the jaw 46 is withdrawn and prevents slipping of the thread. A member 48, Figs. 1 and 8, having two forked limbs moves downwardly to engage the pulled-out thread and depresses it so that jaws 51, 53, Fig. 13, on a knotting-device can be passed between the limbs and above the thread. The jaw 53 is fixed to a rod 52, rotatable within a tube 50 carrying the jaw 51, and arms on the parts 50, 52 pressed apart by a spring 54 keep the jaws closed normally. The jaws can be rotated by means of gearing 57, 58 or moved axially by means of an arm 55 engaging collars on the tube 50. After the initial axial movement referred to above, the jaws are turned through 180‹, Fig. 8, and given a reverse axial movement to draw the thread ends into a loop. A further rotary movement through 270‹ into the position shown in Fig. 9, to twist the loop is imparted to the jaws which are opened at the end of this movement by the engagement of a stop 60 with the jaw 53. An axial movement in the direction of the arrow, Fig. 9, is now given so that the jaws pass over one part of the thread and grip it when the stop 60 is withdrawn. A further rotary movement causes the jaws to draw the gripped part of the thread through the twisted part and form the knot which is tightened by withdrawing the bundle from the machine with one thread end still gripped by the jaws 51, 53.