In PCB, the so-calLED short refers to the PTH hole or NPTH hole whose slot length is less than or equal to 2 times the slot width. For short, L ≤ 2D. L is the slot length of the short slot hole and D is the slot width of the short slot hole. At present, most PCB manufacturers use mechanICal drilling machine to process short slot holes. The deviation of short slot holes has always been a problem faced by PCB manufacturers. Some PCB manufacturers can only change the number of drilling stacks to take into account the deviation of slot holes, which affects production capacity.
The deviation of slot hole brings great trouble to the loading of the client, and the automatic loading of free fall cannot be carried out, so manual plug-in operation is required. In the era of industrial automation, efficiency and cost saving, it is imperative to improve the deviation of short slotted holes.
Key elements of slot hole technology:
The invention aims to provide a method for making short slot holes on a PCB board, so as to solve the problem of deviation of short slot holes in the process of PCB making in the prior art.
Short slot hole method on PCB board: CAM software is used to control the drilling machine to make short slot holes on the pcb board. The short slot hole is designed to rotate 5 degrees counterclockwise according to its own center through CAM software. The drilling machine uses a short slot cutter with a blade length of 4.5mm. The drilling machine uses a 4.5mm short slot cutter to drill short slot holes on PCB board according to the design of short slot holes by CAM software.
When the drilling machine is drilling short slot holes, the drilling parameters, speed parameters and feed speed parameters for making non short slot holes with the same aperture will be reduced by 40%.
For the short slot hole with the hole diameter less than 1.0mm, two chip removal holes are added in the CAN software design. The two chip removal holes are designed at the position where the two sides of the short slot hole are tangent. The calculation formula of the chip removal hole diameter is (L-0.2)/2. In the formula, L is the slot length of the short slot hole, and the minimum chip removal hole diameter is 0.25mm.
In the invention, when receiving a new order from a customer, it is necessary to confirm whether there is a short slot hole with a slot length less than 2 times the slot width. If there is one, CAM production data needs to be designed by turning the short slot hole 5 degrees counterclockwise
The OP shall note the short slot hole in the drilling column of the flow sheet when making the flow sheet.
During drilling operation, a short slotted knife with a blade length of 4.5mm shall be prepared according to the material number MARKed with short slotted holes in the work order.
During drilling operation, the parameters of short slot cutter shall be optimized and confirmed. The drilling parameters, rotating speed and feed speed shall be reduced by 40% with the same aperture parameters of non slot hole.
Rogers local concrete plate structure
The patent technology of the utility model discloses a local structure, including a Rogers local mixed pressure fixing plate, the bottom of the Rogers local mixed pressure fixing plate contacts the top of the mounting plate, the top of the Rogers local mixed pressure fixing plate is fixedly connected with a high-frequency, the two sides of the top of the mounting plate are fixedly connected with a fixed rod, the two sides of the top of the Rogers local mixed pressure fixing plate are fixedly connected with a vertical rod, and the surface of the middle of the vertical rod is fixedly sleeved with a pressure sleeve, The right side of the pressure sleeve is fixedly connected with the side of the high-frequency circuit board. The Rogers local hybrid High Frequency Circuit Board structure pulls the limit sleeve outwards while rotating the telescopic rod, so that the limit sleeve can be smoothly sleeved on the surface of the fixed rod. The compression spring drives the U-shaped clamp to clamp with the clamp boss, while rotating the threaded rod, using the principle of thread propulsion, to drive the clamping plate to constrain the Rogers local hybrid fixed plate, The utility model achieves the effect that the high-frequency circuit board can be disassembled at any time, and effectively improves the service life of the high-frequency circuit board.
Rogers local concrete plate
Rogers local mixed voltage high frequency circuit board is a high strength and stable circuit board with high electromagnetic frequency. Generally speaking, high frequency can be defined as a frequency of more than 1GHz. Under the prEMIse that electronic products tend to be multifunctional and complex, the contact distance of circuit components will be reduced, and the speed of signal transmission will be relatively increased. The following is the increase of the number of wiring and the local shortening of the length of wiring between points, These require the application of high-density circuit configuration and microporous technology to achieve the goal of high frequency. At present, the existing Rogers local hybrid high-frequency circuit board is generally directly welded to the installation circuit board through welding during the installation process, which is not convenient for the cleaning of Rogers local hybrid high-frequency circuit board and later installation and maintenance, thus reducing the service life of Rogers local hybrid high-frequency circuit board.