PCBA Tech - smt placement and high-precision smt placement machine

Electronic components have many performance parameters, among which the main ones related to smt mounting production are:

1. Overall length and width dimensions

The dimensions of the components are hundreds of times different. The smallest chip component 0402 (British 01005) is only 0.4mm*0.2mm, and some connectors can reach more than 120mm in size. Therefore, the structure of the chip head and the performance parameters of the nozzle are affected. The requirements vary greatly, and there is almost no placement machine that can meet the placement of components of all sizes.

2. Overall height dimension

The shape height dimension is also an important placement element. It is related to the placement of the placement head of the placement machine, and the nozzle installation is related to the Z-stroke. The maximum height of the corresponding component of a placement machine or placement head is determined.

3. Lead pitch of components

The lead pitch of integrated circuit packages will also have requirements for placement and placement, especially narrow pitch (or fine pitch) packages, such as QFP with a pitch of 0.3 and BGA with a pitch of 0.4, which can accurately position the placement machine. Degree to request.

4. Weight of components

The weight of components is related to the nozzle structure and vacuum suction requirements of the smt placement machine. The maximum weight of a placement machine or placement head that can mount a component is certain. If it exceeds it, the placement rate will decrease.

5. Surface quality of components

Among the performance parameters of surface mount components, the main factors that affect the mounting process are the surface roughness and height dimensional errors. This effect is mainly reflected in small components, namely 0603 and 0402 chip components. Small components that appear to be exactly the same. In fact, due to differences in the production quality of different manufacturers, or differences in the quality control of different batches of the same manufacturer, the actual dimensions and surface roughness of the components will be different, which not only affects the welding performance of the components, but also Will affect the placement performance.

In the smt patch proofing or processing process, the surface roughness affects the suction force of the vacuum system of the suction nozzle on the component, and in severe cases, it will cause picking failure or throwing.

For placement heads that do not have soft landing technology, the dimensional error of the height of the components may cause picking failure or damage to the components, thereby affecting production efficiency and product quality.

High-speed and high-precision smt placement machine

1 Overview

With the widespread application of surface mount ICs and users’ demand for flexible production, in the mid-to-late 1990s, many placement machine manufacturers introduced high-speed and high-precision placement with the advantages of both high-speed machines and multi-function placement machines. The machine makes it possible to use only one placement machine for the smt production line. A high-speed and high-precision placement machine can complete the placement of almost all components while maintaining a high placement speed. For small and medium-sized enterprises, product R&D departments and scientific research institutes, it will undoubtedly reduce user investment. A cost-effective choice. Even for large enterprises, it is possible to increase production capacity by increasing the number of placement machines, and avoid the use of two placement machines. The benefits of this scheme are obvious whether it is for smt patch proofing or processing production line design and planning, or production line operation and maintenance, so it has become the mainstream of smt production line configuration in the new century.

2. Structural features

The high-speed and high-precision placement machine mainly adopts a composite structure. The composite structure machine is developed from the boom type machine. It combines the characteristics of the turret type and the boom type. A turret type placement head (also called a turntable) is installed on the boom to form a turntable boom type structure. As shown in the figure, the number of nozzles in a single arm is greatly increased,

Structure diagram of boom type placement machine

Strictly speaking, the compound machine still belongs to the boom type structure. Since the compound machine can increase the speed by increasing the number of booms and has greater flexibility, its development prospects are promising