Patent GB-726514-A (GB)
Title: Improvements in bundle tying apparatus
IPC: B65B13/10
Filed: 1953-09-29
Abstract: 726,514. Tying bundles. LUDLOW MANUFACTURING & SALES, CO. Sept. 29, 1953 [May 14, 1953], No. 26721/53. Class 94 (1). [Also in Group XV] A machine for tying bundles which winds one or more turns of twine around the bundle and secures the ends of the wrapped twine by means of a metal clip is provided with a bundle table having fixed and island sections 41, 40, Fig. 1, respectively, and with a wrapping arm 31a, 31b rotatable on an axis 27 parallel to the top of the table. As the arm is rotated to lay the twine around the bundle B, the free end is held by a gripper 61 and after wrapping, the ends of the twine are overlapped in a throat formed in a die mounted beneath the table at one side of the plane of the twine wrap and comprising a fixed member 100, Fig. 9, and a movable member 101 which pivots to the far side of the wrap plane and together with the fixed die member 100 forms a tangential opening 114, Fig. 15, into which is fed edgewise a slug 141 cut from the end of a flat metal strip S which is formed in the die into a clip tightly enclosing the ends of the wrap. After formation of the clip, the gripper 61 releases the end of the twine one side of the clip, is moved over to the opposite side of the clip where it recloses on the other leg of the twine. In this position cutter means 84, 85 mounted on the gripper arms cut the twine, whereafter the gripper returns to its original position for a fresh cycle. General features. The bundle B, Fig. 1, on the table 40, 41 is also supported by a vertical plate 39 and uprights 53 and may be compressed by a top plate 47 whose vertical movement is controlled by a compressed-air cylinder 49. The wrapping arm 31a, 31b is normally held in a position of rest in a recess at the end of an arcuate guide plate 54 the surface of which has a friction lining to bring the arm to rest at the end of the wrapping sequence. The twine T is threaded through the shaft 27 on to a spring-loaded tension arm 33, thence through an eye 36 at the angle of the wrapping arm to a second eye 37 at the end of the arm and from the eye 37 it is led to the gripper 61. The twine-gripper. The combined scissors and gripper device 61 is mounted on a base 62, Fig. 4, secured to a bar 63 mounted on the ends of cranks 64, 65, attached to pins 66, 67 which carry pinions 70 engaging with a rack 71. Operation of the rack results in the movement of the device 61 through the positions shown in dotted lines in Fig. 4. Mounted on the base 62 is a fixed arm 74, Fig. 10, carrying the fixed gripper jaw 74a and the fixed scissor blade 84. The movable jaw 79a of the grippers is formed on the upper end of a link 79 pivoted at 80 to a link 78 which is in turn pivoted to one arm 76b of a bell crank pivoted to a straight link 75 pivoted at 75a on the fixed arm 74 and whose other arm 76a is provided with a roller engageable with a fixed stop 77. A spring 81 connects arm 76a with the tail of the link 79 and a pin 82 on that link is engageable with a stop pin 83 on the link 78. The opening of the gripper device is effected by means of an arm 87 of a bell crank whose other arm 89 is controlled by a cam 91 on the cam-shaft 92. When the scissors-gripper is to be opened arm 87 strikes the roller on the end of crank-arm 76a, the bell crank 76 together with the link 75 move clockwise thereby causing link 78 with the movable scissor blade to move away from the fixed blade. The pin 83 then engages the pin 82 and thereby causes link 79 to move the movable gripper jaw 79a away from the fixed jaw 74a. The spring 81 holds the parts in the open position. The parts are closed by means of an arm 93 also controlled by the cam-shaft 92 which engages the roller on arm 76a from beneath and causes the bell-crank 76 to swing anticlockwise thereby closing, through movements reverse to these described above, the gripper jaws and, shortly afterwards, operating the scissors. The clip-forming die. The fixed die-member 100, Fig. 9, is secured by brackets to a removable plate 103 forming part of the fixed table 41. The movable die member 101 is mounted between wing-brackets 105 which are pivoted to arms 106 fast on a shaft 107. One of the brackets 105 has an extension 105a to which is connected an operating rod 108 and also carries on its outer surface a roller 109 which can bear against a cam-block 110 on the under side of the plate 103. When the overlapping lengths of the twine are ready for clipping the rod 108 moves the die 101 clockwise until the roller 109 engages under the camblock 110, the shaft 107 is then rocked clockwise and the arms 106 move 'the movable die 101 horizontally towards the fixed die 100 until a rib 115, Fig. 15 on the movable die enters a corresponding channel on the fixed die. When the die members are in contact channels 111, 112 in the. movable and fixed die members respectively together form a throat in which the twine ends are held and in which the securing clip is formed. The movable die member has a tongue 113 which moves over the top of the die member 100 and when the members are closed forms, together with that top, an entrance 114 leading tangentially to the throat. Clip-feeding arrangements. The securing clips are formed from slugs 141 cut off from a strip S which is advanced step-wise from an opening in a block 143, Fig. 9, and between upper and lower guides 158 by a feeding block 147 guided by rollers 150, 151 and reciprocated by a rod 152, connected to one end of a lever 153 freely mounted on a shaft 97 and rocked by a link 154 which in turn is operated by a lever 157 from the cam-shaft 92. Spring-urged plates 148 and 144 on the blocks 147 and 143 respectively permit movement of the strip S in the feeding- direction only. At the end of its travel the strip S passes over a fixed plate 160, Fig. 15, under a removable plate 159 until the length to be cut off rests over a slide 162, the plate 159 and the slide 162 being provided with shear bars 161, 163 respectively. The slide is reciprocated in a vertical direction to cut off the slug from the strip S by rack-teeth on the slide which engage similar teeth on an arm 164 operated by levers 165, 169. The slug 141 is then moved through the tangential entrance 114 to the throat 111, 112 to encircle the two twine ends as a cylindrical clip by means of a punch 121 screwed in a forward extension 123 of a slide 120, moved in guides secured to the under-side of the table 41 by means of a pivoted link 124, Fig. 9, which is pivotally connected to one arm of a bell crank 127 whose angle is pivoted to a link 128 with which it forms a toggle. Link 128 is pivotally mounted on a block 129 which has lateral extensions in guide slots 130 and an opening through which an aligning rod 132 projecting rearwardly from the slide 120 extends. The position of the block 129 is adjustable by means of a screw 133, locking screws 135, 137 being provided. A link 138 attached to a lever 139 pivoted at 140 and operated by a cam swings the bell crank 127 to make and break the toggle to move the slide 120 and thereby the punch 121 backwards and forwards. Adjustment of the throw enables the amount of the slug 141 encircling the twines to be altered for twine of different thickness. The strip S has side edges tapering in thickness so that when formed the entrance opening into the slip at each end is slightly bell-mouthed to prevent the clip cutting the twine. Motor-control and driving arrangements. The machine is operated by a motor 170, Fig. 1, driving a man shaft 171, a counter-shaft 172 and through a clutch 175, a shaft 176. The main shaft is also connected through chain and sprocket drive and a one-revolution clutch 185 to a shaft 186 which drives through gearing 187, 188 the cam shaft 92. The clutch 175 is operated by levers from the plunger arm of solenoid 58 which also controls the frame 55 of the winding arm stop plate 54 and a switch 180 and the clutch 185 is operated by the plunger of a solenoid 192 through a bell-crank 189 which carries a roller 193 engageable with a cam 194 on the shaft 92. A spring-loaded foot treadle 195 carries a projection 197 which closes a switch 198 to start an adjustable timer in operation. Motor 170, controlled by a separate switch, runs continuously. The timer causes solenoid 58 to be operated for periods varying in length according to the number of wraps of twine to be laid about the bundle. On energising the solenoid 58 the winding arm stop plate 54 is moved clear of the arm, clutch 175 is thrown in and shaft 176 rotates to drive the winding arm. At the end of the timed period the solenoid is de-energised the winding arm stops rotating and switch 180 is closed. An arm 181 on shaft 176 actuates switch 182, and both switches being closed at the same time solenoid 192 is momentarily energised to throw in clutch 185 so that shaft 186 and thereby the cam-shaft 92 is driven through one rotation. During this rotation the various cam controlled operations described above are conducted in sequence.