747,617. Ligaturing devices. KAMMER, K. April 9, 1953 [April 12, 1952], No. 9608/53. Class 81(2). A device for ligaturing with a double knot the ends of tubular blood vessels is characterised in that supporting means are so arranged that a ligature thread can be disposed thereon as a main loop and an auxiliary loop each having a slip knot, and are mounted for sliding movement relative to and through a carrier or head to pass the main loop over the vessel to be ligaturedwhich is gripped by clamping means on the device-and release it and the auxiliary loop, the ends of the thread being so resiliently anchored that on transfer and release of the loops the tension in the thread is automatically maintained to tighten the main loop on the vessel and effect the knotting operation. As shown, Figs. 1, 2, a device for ligaturing blood vessels which are to be severed comprises a casing 30 in which is mounted a fixed U-shaped strap member 21 and head piece 22. This latter piece is suitably apertured for the slidable passage therethrough of a lug 3, pins 9 and cutting devices 27 and it also accommodates a lug 6 to which is joined an operating handle 7. The lug 6 may slide longitudinally of the device in slots cut in both the piece 22 and the casing 30. Branching out from the casing are rods 16, 17, around which are disposed springs 18, 19, and along which may slide bushes 14, 15. Slidable centrally through the piece 22 is a beak-like clip comprising parts 1, 2, the latter part being pivoted to the former at 5 and also being integrally connected with the lug 6 and handle 7. This clip is integrally formed with the lug 3 and a rod 4 the rear end of the latter passing through the member 21. A suitably shaped plate 24 is disposed against the rear face of the piece 22 the cutting devices 27 being provided with slots 28 in which projections 29 from the plate may slide. The plate is also formed with apertures through which extensions of pins 9 may slide and through which the rod 4 may pass. A spring 23 is disposed around the rod 4 between the plate 24 and the member 21. A ligaturing thread 8 is applied to the device as shown in Fig. 2 it being so wound in loops 11, 10, around the pins 9 and the clip 1, 2, that if a sudden force were applied to its ends then a double knot could be formed. The ends of the thread are passed under blades 26 of the cutting devices 27 and are then securely fixed to the bushes 14, 15 the latter being pushed up the rods 16, 17, against the springs 18, 19, so that when the thread ends are fixed the thread is under tension. Operation of the device is effected by movement of the handle 7 initial downward movement causing the clip to grip the blood vessel. Subsequent handle movement causes the device other than the clip 1, 2, lug 3 and rod 4 to move upwards thus moving the clip, lug and rod relatively downwards through the piece 22 an abutment at the lower end of the lug 3 causing the plate 24 to move against the spring 23. When the top surface of the piece 22 has moved over the pointed end of the clip 1, 2 the first knot is tied arotmd the blood vessel as the loop 10 is cast off the clip 1, 2. The plate 24 then acts upon the enlarged lower ends of the pins 9 such that they are relatively withdrawn below the top surface of the piece 22 this effecting the sudden contraction of the loop 11 and the formation of the second knot. Further movement relatively downwards of the plate 24 causes its projections 29 to abut against the ends of the slots 28 in the cutting devices 27 thereby moving the blades 26 to cut the thread 8. On releasing the handle 7 the spring 23 causes the movable parts of the device to return to the position shown in Fig. 1. In a further embodiment, Fig. 10, the casing 30 is provided with slots 36, 37, in which stub axles securing buttons 33, 34 to a U-shaped sliding member 32 slide. This member is disposed, prior to the ligaturing operation of the device such that the buttons 33, 34, are at the top of the casing, a spring-loaded button 39 is projecting through a hole 42 in the casing wall and a spring 31, located between the plate 24 and the bottom of the member 32, is compressed. The rod 4 extending from the clip is bored to accommodate a spring 23<SP>1</SP> this spring bearing at its lower end against a piston-like member 45 disposed at the end of a rod 44 abutting at its other end the casing 30. In the pre-ligaturing position of the device, i.e., when the button 39 is engaged in the hole 42 and has pressed against it an indent 40 formed in a leaf spring member rivetted to the casing, the thread 8 is wound in pre-knotting formation around the pins 9 and clip 1, 2, and attached at its ends to the buttons 33, 35. The indent 40 is then pushed and the thread 8 is tensioned by the spring 31 tending to move the buttons 33, 34 away from the top surface of the piece 22. Operation of the device is through a ring 7<SP>1</SP> which is similar to the handle 7 shown in Fig. 1. Initially the clip 1, 2, is withdrawn below the top surface of piece 22 and the first knot formed. Then an abutment 43 engages the plate 24 and causes the pins 9 to be withdrawn thus forming the second knot. The plate projections 29 then operate the cutting devices so severing the knotted thread. The spring 23<SP>1</SP> returns the device to its pre-ligaturing position. To automatically open the clip 1, 2, a raised portion 46, Fig. 9, is disposed on the casing 30 which slips under the relatively downwardly moving handle 7<SP>1</SP>. In a further modification the loop 10 is disposed around a sleeve projecting from the piece 22 and concentrically arranged around the clip 1, 2, such that the loop is contracted suddenly from a circle of large diameter to a knot instead of being gradually contracted as it is when slid from the tapering clip. Fig. 11 shows an apparatus for feeding pre-formed looped threads 8 on to the upper surface of the head piece 22. This apparatus comprises a holding member 48 for the ligaturing device and a rod 51 upon which is suspended in an inverted position a bushed flange 53 having depending sleeves 54, 55 which, when the ligaturing device is in charging position, are so located as to cover the clip 1, 2 and pins 9 of the device. Threaded upon the sleeves 54, 55, is a thread magazine comprising a series of plates 56 between each of which is disposed in a pre-formed looped condition a thread 8. Clip members 57, Fig. 14, are punched from each plate and these hold the ends of the thread. The threads are pushed from the feeding apparatus on to the top surface of the head piece 22 of the device when required. In a modified feeding apparatus the thread magazine is arranged to project upwardly from the foot of the apparatus the ligaturing device in this instance being held clip down for charging.