Principle of die-cutting machine

Gantry
The component feeder and substrate (PCB) are fixed, and the chip head (installed with multiple vacuum suction nozzles) moves back and forth between the feeder and the substrate to remove the component from the feeder. After adjusting the position and direction of the component, it is then attached to the substrate. Due to the installation of the patch head on the X/Y coordinate moving crossbeam of the arch type, it is named.
The adjustment method for the position and direction of components in the arch mount mounting machine:
1. The mechanical centering adjustment position and the suction nozzle rotation adjustment direction can achieve limited accuracy, and later models have no longer adopted this method.
2. Laser recognition, X/Y coordinate system adjustment of position, and nozzle rotation adjustment of direction can achieve recognition during flight, but cannot be used for ball grid array element BGA.
3. Camera recognition, X/Y coordinate system adjustment of position, suction nozzle rotation adjustment of direction. Generally, the camera is fixed, and the mounting head flies over the camera for imaging recognition, which takes some time compared to laser recognition. However, it can recognize any component, and there are also phase recognition systems that achieve recognition during flight. There are other sacrifices in terms of mechanical structure.
This form is limited in speed due to the long distance the pasting head moves back and forth. Generally, multiple vacuum suction nozzles are used to simultaneously extract materials (up to ten) and a double beam system is used to improve speed. That is, the adhesive head on one beam is used to extract materials while the adhesive head on the other beam is used to place components, which is almost twice the speed of a single beam system. However, in practical applications, it is difficult to achieve the conditions for simultaneous material retrieval, and different types of components need to be replaced with different vacuum suction nozzles, resulting in time delays in replacing the suction nozzles.
The advantage of this type of model is that the system structure is simple, can achieve high accuracy, and is suitable for various sizes and shapes of components, even irregular components. The feeder can be in the form of ribbon, tube, or tray. Suitable for small and medium-sized batch production, and can also be combined with multiple machines for large-scale production.
Turret type
The component feeder is placed on a single coordinate moving feeder car, and the substrate (PCB) is placed on an X/Y coordinate system moving workbench. The patch head is installed on a rotating tower. During operation, the feeder car moves the component feeder to the picking position, and the vacuum suction nozzle on the patch head takes the component at the picking position. The PCB is rotated to the patch position (180 degrees from the picking position) through the rotating tower, and the position and direction of the component are adjusted during the rotation process, Place the component on the substrate.
Adjustment method for component position and direction:
Camera recognition, X/Y coordinate system adjustment of position, suction nozzle self rotation adjustment of direction, camera fixation, film placement head flying over the camera for imaging recognition.
Generally, there are more than ten to twenty patch heads installed on the turret, with 2-4 vacuum suction nozzles (older models) to 5-6 vacuum suction nozzles (existing models) installed on each patch head. Due to the characteristics of the turret, the actions are refined, such as selecting and replacing suction nozzles, moving the feeder into position, picking components, component identification, angle adjustment, workbench movement (including position adjustment), and placing components, all of which can be completed within the same time cycle, achieving true high speed. The fastest time cycle is 0.08-0.10 seconds per component.
This model is superior in speed and suitable for mass production, but it can only use components packaged in strips. If it is a tightly packed, large integrated circuit (IC) with only tray packaging, it cannot be completed, so it also depends on other models to cooperate together. This type of equipment has a complex structure and is expensive, with the latest model costing around US $500000, which is more than three times that of the arch type.
constitute
There are many types of current SMT machines, but their overall layout is similar whether it is a fully automatic high-speed SMT machine or a manual low-speed SMT machine. The fully automatic SMD mounting machine is a high-precision automated equipment controlled by a computer that integrates optical, mechanical, and electrical components. It mainly consists of a rack, PCB transmission and bearing organization, driving system, positioning and centering system, mounting head, feeder, optical recognition system, sensor, and computer control system. Through functions such as suction displacement positioning placement, it completes the rapid and accurate installation of SMD components.
frame
The rack is the foundation of the machine, and all transmission, positioning organization, and feeder are firmly fixed on it, so it is necessary to have sufficient mechanical strength and rigidity. Currently, SMT machines come in various forms of racks, primarily including all cast and steel plate welding. The first type has strong comprehensiveness, good rigidity, minimal deformation, and is stable during operation, usually applied to advanced computers; The second type has the characteristics of simple processing and low cost. The specific layout of the machine frame depends on the overall description and load-bearing of the machine, and it should be smooth, easy, and vibration free during operation.
PCB transmission and bearing organization
The conveyor organization is an ultra-thin belt conveyor system placed on a guide rail, usually installed at the edge of the trajectory. Its function is to deliver the PCB to the predetermined position, mount it, and then send it to the next process. The transmission organization is mainly divided into two types: whole type and segmented type. In the whole type method, the entry, placement, and delivery of the PCB are always on the same guide rail, and a limit block is selected to limit it. The positioning pin is positioned upwards, and the compression organization compresses the PCB. The support rod on the support platform is moved upwards to support and complete the positioning and fixation of the PCB. The positioning accuracy of the positioning pin is relatively low, and optical systems can also be used when high accuracy is required, but the positioning time is longer. The segmented type is usually divided into three sections. The first section is responsible for accepting the PCB from the previous technology, the center end is responsible for positioning and pressing the PCB, and the latter section is responsible for sending the PCB to the next process. Its advantage is to reduce the PCB transmission time.
Drive system
The drive system is the key organization of the SMT machine and the primary objective for evaluating the accuracy of the SMT machine. It includes the XYZ transmission layout and servo system, and its functions include supporting the movement of the SMT head and supporting the PCB bearing plane.