A surgical instrument, comprising: a part of the handle (200, 510) a driving member (272), a part (200, 512) of the body that extends distally from the part of the handle and defining a first axis longitudinal； a movable handle (516) arranged in the part of the handle and in mechanical cooperation with said drive member； a tool set (17) that includes an anvil, a cartridge assembly and a contact surface, wherein the tool set is supported adjacent to a distal end of the body part； a drive beam (750) that includes a plurality of layers (750a-750e), which has at least one inner layer and two outer layers, at least one layer has a proximal application part disposed adjacent to a proximal end thereof and which is configured to be applied in a part of the drive member； a closure apparatus arranged adjacent to a distal end of the drive beam configured to be applied to the contact surface of the tool assembly, whereby at least a partial actuation of the movable handle moves the closure apparatus distally until application with the contact surface to approximate the anvil and the cartridge assembly in which each of the plurality of layers of the drive beam includes a plurality of cuts (770) disposed therethrough, where the cuts of the outer layers are aligned with each other； and characterized in that at least one of the drive beam layers is adhered to an adjacent layer of the drive beam by means of at least one welding point (781) and that only the two outer layers (750a, 750e ) are attached to the closing apparatus (760) and because the two outer layers are attached to the at least one inner layer.Un instrumento quirúrgico, que comprende: una parte de la empuñadura (200, 510) un miembro de impulsión (272), una parte (200, 512) del cuerpo que se extiende distalmente desde la parte de la empuñadura y que define un primer eje longitudinal； una empuñadura móvil (516) dispuesta en la parte de la empuñadura y en cooperación mecánica con dicho miembro de impulsión； un conjunto de
