Micro-drill driving device with adjustable stroke

Abstract

The invention provides a micro-drill driving device with adjustable stroke, and belongs to the technical field of precision machinery. The driving device comprises a shell, a middle sleeve and a plunger, the middle sleeve is fixed in the shell; an air inlet channel is formed between the middle sleeve and the shell; a piston rotationally connected with the inner wall of the middle sleeve is arranged at the upper end of the plunger; an impeller is arranged in the middle of the plunger; an adjusting sleeve is connected between the lower end of the plunger and the middle sleeve; a driving air cavity is formed between the upper end of the adjusting sleeve and the lower end of the piston; the middle sleeve is provided with a plurality of air inlet holes communicating with the driving air cavityand the air inlet channel. An airflow reciprocating channel with the upper end penetrating through the upper end face of the plunger is formed in the plunger, a cover plate for blocking an opening inthe upper end of the middle sleeve is fixedly connected to the top of the middle sleeve, a compressed air cavity communicating with the airflow reciprocating channel is formed between the lower end face of the cover plate and the upper end face of the plunger, and multiple functional holes communicating with the airflow reciprocating channel are formed in the middle of the plunger; a micro-drill mounting head is arranged at the lower end of the plunger. The driving device has the advantages of high operation efficiency and the like.

Description

technical field [0001] The invention belongs to the technical field of precision machinery, and relates to a micro-drill driving device with adjustable stroke. Background technique [0002] PCB board is also known as printed circuit board and printed circuit board. It is an important electronic component, and it is also the support body of electronic components and the carrier of electrical connection. Due to the small size, thinness, and precision, the drill bits such as micro screwdrivers and milling cutters used for drilling and milling are also becoming more refined, and the requirements for the driving mechanism that controls the rotation and expansion of the drill bit are also getting higher and higher. [0003] Specifically, the refinement of the drill bit reduces its strength, and problems such as breakage, damage, and deformation seriously affect the service life of the drill bit; the traditional drill bit drive mechanism is an integration of multiple control mechan...

AI Technical Summary

Problems solved by technology

[0003] Specifically, the refinement of the drill bit reduces its strength, and problems such as breakage, damage, and deformation seriously affect the service life of the drill bit; the traditional drill bit drive mechanism is an integration of multiple control mechanisms, which is suitable for automated production. It takes up a lot of space, and generally includes a rotary drive unit that drives the micro-drill to rotate and a knife-feed drive unit that controls the longitudinal feed / exit of the micro-drill. In the automated production process, it is not only necessary to coordinate the two drive units, but also to reduce the Due to the impact force of the drill bit, the drill bit always maintains a certain rotation speed, and the continuous processing of the PCB board is realized through longitudinal reciprocating motion and the translation and switching of the PCB board. The drill bit is always in a state of high heat and high intensity, which has a great impact on the service life of the drill bit.

[0004] In addition, during the processing, whether it is entering or exiting the tool, the drill directly contacts the PCB board at a relatively constant high speed (neglecting the change of the speed when it is in contact with the board, it can be assumed that its speed is constant). The method causes the following problems: 1), the instantaneous cutting heat will cause local thermal deformation to the PCB processing part; 2), the greater impact force will lead to the increase of PCB positioning difficulty and the positioning strength of PCB board (especially the micro PCB board during the processing process is not enough) 3) There is no longitudinal buffer between the PCB board and the drill bit, which causes high-strength "cutting" of the PCB board, which makes the PCB board hole or slot edge burrs / burrs larger, usually requiring two Repairing and deburring for a second time will have a negative impact on processing efficiency, processing accuracy and processing quality; 4) In the initial stage of tool feeding, since the micro-drill has not yet achieved "thread-eating" between the micro-drill and the plate, the resistance at the end of the micro-drill makes the coaxiality Negatively affected, it is easy to cause severe wear, edge chipping and knife breakage of the cutter head. Due to the existence of the rake angle, rear angle, front angle and helix angle of the micro-drill, the micro-drill is subject to greater stress off the axis, and it is easy to The deformation of the mid-section of the micro-drill will greatly affect the service life and processing accuracy of the micro-drill after the coaxiality is affected

[0005] Heat dissipation is also an important factor to prolong the service life of micro-drills. The existing equipment that drives the rotation of micro-drills does not have the means to effectively dissipate heat from micro-drills

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