KNOT-TYING HEAD

Advantageously, the knot-tying head allows a filament to form a path around an essentially cylindrical space, such that once the filament is tautened, it forms a knot on a part. [0013] In a particular embodiment, the filament is a tape. Tape will be understood as a filament with an essentially rectangular section, the choice of this type of filament being advantageous because once the knot is tied, the loop around the part is flat and does not project too much from the profile of the part. [0014] In another particular embodiment, the at least one first body and the at least one second body are attached in a hinged manner. [0015] In the present document, hinged attachment will be understood as a device that allows attaching two elements such that they can rotate about a shaft, an example being a hinge. Advantageously, the hinged attachment allows opening and closing the knot-tying head to make it easier to position the part in the hollow space. [0016] In an additional particular embodiment, the path of the conduit is configured for making a double capstan knot. [0017] Without prejudice to other paths configured for forming other knots, the double capstan knot allows securely fixing, for example, a bundle of electrical cables, without requiring a path that is too complex. It is possible to provide other paths for forming other knots by means of heads manufactured specifically for each knot. [0018] In another particular embodiment, the at least one first body and the at least one second body comprise at least one opening configured for the filament to enter or exit the conduit. [0019] This opening or these openings allow the filament to be inserted and to exit once the path is completed. Advantageously, the filament can be tautened through this opening or these openings by means of pulling on both ends of the filament at the same time. [0020] In yet another particular embodiment, the at least one opening is arranged substantially in the portion in which the at least one first body and the at least one second body are hinged. [0021] Advantageously, this arrangement makes it easier to implement an automated system for making the knot. [0022] In another particular embodiment, the at least one first body and the at least one second body comprise two openings and are essentially communicated with one another. [0023] Advantageously, the existence of two openings allows having an independent inlet and outlet for the filament; furthermore, the communication between the two openings, for example by means of a groove, allows tautening the ends of the filament more easily once the filament passes into the hollow space. [0024] In a second inventive aspect, the invention provides a knot-tying system comprising: a knot-tying head according to any of the preceding claims, a filament feed device, and a filament pulling device. [0025] Advantageously, the filament feed device allows providing the filament required for forming a knot on the part, and the filament pulling device allows producing pulling or compression on the filament or on another similar element that is introduced into the conduit. [0026] In a particular embodiment, the filament feed device is a reel. [0027] In a particular embodiment, the system comprises a filament cutting device and a filament tautening device. [0028] Advantageously, the cutting device allows separating one end of the filament threaded into the conduit of the spool from which the system is fed, whereas the tautening device allows producing pulling on both ends of the filament for the purpose of securing the knot around the part. [0029] In another particular embodiment, the system comprises an electronic control module for controlling the devices of the system and an actuator for the filament pulling device. [0030] Advantageously, the control module allows carrying out the knot-tying process automatically, according to pre-programmed instructions. The actuator furthermore allows putting the pulling device in motion, for example by transmitting a rotation torque to the reel containing the filament. [0031] In another particular embodiment, the system comprises a power source. Advantageously, the power source supplies power to the devices and to the control module and allows the system to be used independently from an external power supply source. [0032] In an additional particular embodiment, the system constitutes a portable system. The system can therefore be handled by an operator directly at the site where the part is located, without having to take the part to an established work station. [0033] In a third inventive aspect, the invention provides a method for forming a knot with a filament around a part, comprising the following steps: providing a knot-tying system, placing the part in the knot-tying head, closing the first body and the second body, threading a guide for the filament into the conduit, attaching one end of the filament to the guide, threading the filament along the entire conduit of the head by means of pulling the guide, separating the end of the filament from the guide, tautening the filament around the part, and cutting the end of the filament attached to the filament feed device. [0034] Throughout the present document, threading will be understood to consist of the action of introducing a filiform element into a cavity, for example into the conduit of the head. Guide must be understood as a filiform element and having certain rigidity, similar to the filament but without being consumable, and capable of transmitting compressive loads in order to, advantageously, be simply introduced into the conduit of the head. Furthermore, said guide comprises at one or both ends means for attaching the filament to the end of the guide, being possible to separate it from the guide at will. [0035] Advantageously, the described method can be carried out by hand or automatically, controlled by means of the control module. [0036] In another particular embodiment, the threading is done with the help of a pulling device. The pulling device therefore serves not only to apply pulling on the filament or guide, but it also can be used for threading the guide or the filament into the conduit. [0037] In a final particular embodiment, the tautening is done with the help of a pulling device. Advantageously, the pulling device allows transmitting pulling or compression to an element threaded in the head, for example the filament, which in this embodiment is tautened by means of said device for securing the knot. [0038] All the features and/or steps of methods described herein (including the claims, description and drawings) can be combined in any combination, with the exception of those combinations of such mutually exclusive features.