Automated Selective Soldering Machine – Spark-400 Automated SMT Laser Selective Assembly System

Automated Selective Soldering Machine – Spark-400 Automated SMT Laser Selective Assembly System : BeamWorks Spark-400 – Automated Selective Soldering Machine

Spark-400 is a laser-based automated selective soldering machine for SMT line. The automated selective assembly and rework system addresses some of the key technical issues and concerns of PCB assembly and rework.

Concern-1: Selective assembly of through-hole components such as sockets and connectors. These problems are going to remain as long as through-hole components will remain in the SMT industry. Remember, not all electronic components are available as SMD (Surface Mount Device).

In a mixed PCB assembly, through-hole components are soldered selectively by three methods:

  1. Wave soldering using a specially designed fixture
  2. Paste-in-hole process
  3. Hand soldering.

When selective wave soldering and paste-in-hole process are not technically feasible, hand soldering using soldering station or iron is used as the last option. Hand soldering is slow, expensive and operator-dependent, resulting in inconsistent solder joints. Hand soldiering is susceptible to external and internal damage leading to unreliable PCB Assembly even after passing electrical tests.

Concern-2: Through-hole components are not just the reason behind selective soldering. Another reason for automated selective soldering is increasing use of selective RF shield soldering, such as in mobile cell phones. While some of these RF shields can be reflow soldered in convection ovens, many of them still need to be soldered by hand. Even shields that can be soldered in convection ovens require hand soldering for removal to allow rework of components shielded by them. Additionally, there are many surface mount connectors, especially those with leads on each side of the board that need to be selectively soldered.

Concern-3: Moisture-sensitive devices must be baked before soldering to prevent package cracking, commonly referred to as popcorning. Reworking an expensive device can be painful and very expensive. In conventional methods, to rework an individual component, the entire PCB assembly must be baked for 24 hours to seven days. This increases chances of potential damage to the board, especially while removing large components such as fine pitch, plastic leaded chip carriers (PLCC), ball grid arrays (BGA) and small components such as chip scale packages (CSP). This problem gets worse with use of lead-free solder that have a high melting points compared to leaded solder.

Spark-400: Automated Laser Selective Soldering Machine

As explained above, the major concerns of modern PCB assembly and rework are – selective assembly / rework of through-hole components, missing components, moisture-sensitive surface mount components, lead-free soldering, and soldering of RF shields.

Spark-400 automated lased-based selective soldering machine is perfect solution to all these concerns. This laser assembly machine has the ability to selectively assemble any component thus addressing these technical concerns. It is a laser soldering and assembly machine that can perform all the assembly functions from solder paste dispensing and flux application to inspection and rework. This machine dispenses solder paste with positive force displacement to accurately control paste volume. Various pick-up heads pick up components from as small as 0402 to as large as BGAs and fine pitch. Multiple diode lasers selectively or simultaneously solder in milliseconds. Because laser cannot see BGA, CSP and flip chip balls, the laser beam width is increased to simulate an oven profile to reflow hidden solder balls. The system can also perform rework and inspection functions. There is no need for programming because computer-aided design (CAD) data is used for all assembly functions – paste dispensing, placement, soldering and rework. Components such as fine pitch do not have to be baked because the package does not get hot, only the leads do.

Beamworks Spark-400 machine can be used for both high-volume and low-volume applications. For example, if it is used only as a soldering machine, multiple lasers can keep up with the high-volume pick-and-place machine in the line. It can also be used to selectively assemble components in a high-volume line. Examples include missing components in an already assembled board or an RF shield in a high-volume line. In low-volume applications, it can assemble all components in quick-turn applications.

While this machine can be used for low-volume, quick-turn applications, it is well suited for unique applications where conventional processes either are not technically feasible or are too expensive. Additionally, because reflow time for each joint can be individually programmed, the heat input for each joint can be precisely tailored to meet the needs of joints connected to power and ground planes or heat sinks. Because this machine measures soldering time in milliseconds (as opposed to seconds), the inter-metallic thickness is under 1 mm (or less than 40 m”. Compare this to 500 m” or more in other soldering methods), greatly improving solder joint reliability.

Spark-400 - Automated Selective Soldering Machine

Spark-400 – Automated Selective Soldering Machine

BeamWorks Spark-400: Addressing Automated Selective Soldering / Assembly Concerns

Spark 400 from BeamWorks is an automated selective assembly system that performs all functions of a typical SMT line – solder paste dispensing, component placement, laser soldering and inspection. Soldering and inspection functions are performed concurrently to provide real-time feedback on solder joint quality. This is one of its kind machine that automatically stops soldering when desired solder joint quality is achieved. It tailors heat input to a specific component as well as to a specific lead. If a certain lead of a given component is connected to power or ground plane, the laser soldering time is longer for that lead than the adjacent lead not connected to a heat sink.

Because the machine dispenses paste, a partially assembled board does not pose any problems as it would if a stencil were used. It does not require separate programming for dispensing, placement and soldering. Paste dispensing is done either as dots or a thin strip of paste. Then, using the same computer-aided design (CAD) data, it places components and quickly solders them using four diode lasers. During the process, the selective assembly of missing surface mount components does not affect in any way the components that already have been assembled on the conventional SMT line. Also, because the heat source for reflow is a diode laser, the moisture-sensitive components already assembled (or to be assembled) do not require baking.

Missing components have been one reason for quality and delivery problems in manufacturing. Using Spark-400 selective automated assembly system from BeamWorks provides a cost-effective system for addressing this common industry problem.

Video: BeamWorks Spark-400 Automated Selective Soldering Machine

Spark-400: Typical Application

  • Quick Turn Prototype Assembly
  • NPI and Small Lot Production
  • Complete SMT Assembly Line for Engineering Labs
  • Automated Mass Rework, Including BGAs
  • Selective Assembly of Planned (and Unplanned) Missing SMT Components
  • Selective Assembly of: SMT Connectors (Single and Double Sided), RF Shields, Through Hole Components (Paste in Hole Process), Heat Sensitive Components, Optical Components & Smart Cards, Moisture Sensitive Components
  • Lead-Free High Temperature Soldering
  • Re-balling All Types of BGA
  • Flip-Chip & CSP Assembly
  • Unique & special Applications

Spark-400: System Features

  • Vision System for Auto Alignment Using Board Fiducials
  • Using Standard CAD and BOM Files and Utilizing On-board Component Library of Components Geometry
  • Win 2000 Operation System and Comfortable GUI
  • Simultaneous Operation of 4 Lasers Provides High Soldering Throughput
  • Full SMEMA Support Allows In-Line Operation
  • Either Stand Alone or In-Line Operation

Spark-400: System Benefits

  • Closed Loop Temperature Controlled Soldering
  • No Stencil Required
  • Flexible Operation Allows for Fast Turn Around
  • Precise Heating without impacting Adjacent Components
  • Auto Load of CAD and BOM Data
  • Small Footprint
  • Thin Intermetallic Layer for Improved Reliability
  • No Baking of Moisture Sensitive Components
Programmable Power, Laser Heat Source
Laser Type(4 units) CW (Continuous Wave) Diode Laser/ Fiber
Coupled
915-940 nm, 30W Max Power,0.8 mm (0.03”)
Fiber Core Diameter
Cooling System Thermo-Electric Based Closed Loop Temperature Controlled
Laser Lifetime 10,000 Hours (Min)
Laser Controller Current source-Up to 100 Amperes Computer Controlled
Machine Specifications
Dimension Width 1,000 mm
Depth 1,300 mm
Height 1,600 mm
Weight 900 kg 980 kg shipping weight
Power Supply 230VAC, 50 Hz. 32Amp Single Phase
110VAC, 60 Hz. 32 Amp Double Phase
Pneumatics 80 PSI. 10 CFM, 280
liter/minute
Clean, Dry Filtered Air
Control System Pentium IV min. Win 2K Operation System
Color Monitor 17” Flat Panel Display
Keyboard and Track Ball Built-In
Technical Specifications
Solder Paste Dispensing Rotary Positive Displacement Pump
with an Archimedean Screw Dispensing Capability. Capability to Dispense Solder Paste or Epoxy Dots and
Lines
For Accurate and Controlled Paste
Deposit Line Dispensing
: Down to 0.4 mm (0.016”)
Pitch Dot Dispensing: Down to 0.3 mm (0.012”) in Diameter
Pick & Place Feeder Slots 29 Standard
Matrix Tray Handling 3 Standard (Configuration Dependant)
Up to 20 in a Magazine Handler (Optional)
Component Handling Throughput Up to 75 mm (2.95”) and Down to 0402
Vision Capability Up to 1,000 CPH
Matrox Based Algorythms
Laser Soldering Module 4 Laser Diodes
Independent Optical System for Each
Laser to Direct X, Y Movement Closed
Loop Operation Utilizing IR Sensors to Control Solder joint Temperature
30 Watt Each
Input Data Standard CAD Files
Combined CAD & BOM
Converted P&P Machine File
Components Library Size jedec Tray
Library Size
Also Requires BOM File
Using On-Board File Converter >2000 SMT Components 125 trays
General Specifications
Board AlignmentVision System

(Down Looking Camera)

Camera EIA (RS 170) 768×494 Pixels
FOV 6×4 mm (0.24×0.16”) Field Size
Depth of Field 8 mm (0.31”)
Illumination System Vertical Ring. Red LEDs
ComponentAlignment Vision

System

(Up Looking Camera)

Camera ELA (RS 170) 768×494 Pixels
FOV 14×10.5 mm (0.55×0.41”) Field Size
Depth of Field 8 mm (0.31”)
Illumination System Vertical & Oblique Ring. Red LEDs
Conveyor System Max Board Dimensions Board Length: 508 mm (20”)
Board Width: Up to 406 mm (16”)
Configuration dependant
Min Board Width 28 mm (1.10”)
Min Board Thickness 1.0 mm (0.04”)
Max Board Thickness 4.0 mm (0.16”)- for greater board
thickness use carrier
Edge Clearance 4.5 mm (0.18”)
Top Side Clearance 46 mm (1.81”)
Bottom Side Clearance 32 mm (1.26”)
x-y System x-y Mechanism Linear Motor Driven System
Motion Accuracy (3σ) 2 mil
Motion Repeatability (3σ) 0.8 mil
Max Speed 1.5 m/sec (4.9”/sec)
Max Acceleration 4 m/sec² (13’/sec²)