Endoscopic biopsy forceps include standard type, side-opening type, head-end needle type, circular cup-shaped type, tooth-shaped cup-shaped type, and so on. They are mainly connected by laser welding, which can be achieved by continuous or pulsed laser beams. Laser radiation heats the surface to be processed, and the surface heat spreads inward through heat conduction. By controlling laser parameters such as pulse width, energy, peak power, and repetition frequency, the workpiece is melted to form a specific pool.
The energy conversion mechanism is completed through the "small hole" structure. Under sufficient power density laser irradiation, the material evaporates and forms a small hole. This vapor-filled small hole is like a black body that absorbs almost all of the incident light beam energy. The equilibrium temperature inside the hole is about 2500°C, and the heat is transferred from the high-temperature hole wall to melt the metal surrounding the hole cavity. The high-temperature steam continuously evaporated by the wall material under the irradiation of the light beam fills the small hole, and the wall surrounding the small hole is surrounded by melted metal, and the liquid metal is surrounded by solid material. The flowing liquid outside the hole wall and the surface tension of the wall layer are balanced with the continuous vapor pressure generated inside the hole cavity, maintaining dynamic equilibrium. The light beam continuously enters the small hole, and the material outside the small hole flows continuously. The small hole is always in a flow-stable state as the leading light beam moves forward at a certain speed. That is to say, the small hole and the melted metal surrounding the wall of the hole move forward with the leading light beam, and the melted metal fills the gap left after the small hole moves away and then condenses, forming a weld.
All of the above processes happen so quickly that the welding speed can easily reach several meters per minute. This is the mechanism we see for the formation of screw cavities of biopsy forceps. Therefore, once the thread cavity of the biopsy forceps is broken, it cannot be repaired by ordinary welding, and metal burrs will be formed. In recent years, most biopsy forceps have adopted a rigid four-bar linkage structure, making the use of biopsy forceps more convenient. Here we pay tribute to the tireless engineers, who have devoted a lot of effort from invention to market application of a product.
The key to using biopsy forceps is to master the strength of your hands. I am used to using the ring finger, middle finger, index finger, and thumb to cooperate with the use of biopsy forceps. When using endoscopic biopsy forceps, the force should be moderate, and avoid using excessive force to switch. This not only cannot grasp the diseased tissue well but also easily damages the biopsy forceps.
The use of biopsy forceps in mastering strength is the foundation of various accessories. You may not feel it during ordinary biopsy, but when you are removing foreign bodies, especially coins, when using alligator forceps to pick up coins, if the alligator forceps are opened too much and used too much force, it is difficult to firmly clamp the coin. Open the forceps slightly larger than the edge of the coin, and try to go over the edge of the coin. Then clamp the coin firmly with force. Pay attention to practicing opening the biopsy forceps to any size and self-feeling.