Article was already bookmarked.
The purpose of this utility is to facilitate entering package dimensions that include:
Thickness of the package.
Narrowest length of the package.
Longest length of the package.
Alignment offset that will obtain the best measurements during a job session.
Alignment tolerance value based on the narrowest package dimension and common manufacturing variances.
For instructions on how to use the Automated Package Measure Utility, click here.
The utility uses the CyberOptics laser align camera to obtain measurements of the package thickness, narrowest length and longest length. The utility will also use the camera to acquire a package profile. The profile consists of “measurement slices” obtained starting from the top of the package and ending with the bottom of the package. This profile is then used to determine the alignment offset that will obtain the best package measurements during teaching and a job session. The accuracy of the utility is limited by the hardware and the package that is being measured.
Examples that may exaggerate inaccurate results are:
Bent leads on the package.
Dirty CyberOptics laser align camera.
Large "runout" on the nozzle.
Using an incorrect nozzle size for the package.
The nozzle to laser align camera laser stripe is not at a right angle.
The auto measure process consists of multiple stages and is described below:
Learning the location of the package.
The location is comprised of the X-axis and Y-axis coordinates, the Z-axis height of the package, and the package’s rotation orientation. This is necessary so that the package can be picked and then placed in its original orientation when the process has completed.
It is very important that the nozzle be as close to the center of the package as possible when teaching its location so that the utility may obtain the best results. If the nozzle is too close to the edge of the package, the utility may not be able to determine the top of the package accurately.
Learning the top of the package.
The nozzle's spring will compress when vacuum is engaged and a package is attached to the nozzle. The amount of spring compression depends on the amount of wear to the nozzle. Because the spring compresses, the home position is not the top of the package. Therefore, the top of the package must be located with this stage of the process. A side effect of this stage is that the spring compression is recorded in the log file. This information can be used to determine when the nozzle will need to be replaced.
Learning the narrowest length and longest length of the package.
During this stage, the package is rotated to determine the optimal pre-rotation orientation. The orientation will also provide that the narrow length of the package will be measured first by the laser align camera. According to CyberOptics laser align camera documentation, measuring the narrow length first results in a better measurement of the package.
According to CyberOptics documentation, the maximum package size that the camera can measure is a 30mm X 30mm package. Anything outside of this range will cause the utility to fail and to abort the process.
Learning the bottom of the package to calculate its thickness.
A package can be too thick to be measured by an Autohandler. The user will be presented with an appropriate dialog if the package is too thick to be measured by an Autohandler.
The BP-4000 series Autohandler has a smaller package thickness range capability than the BP-3000 series Autohandler. Therefore, a thick package that is successfully measured by the BP-3000 series Autohandler may present a dialog on a BP-4000 series Autohandler.
Scanning the entire package from top to bottom, every 2 thousandths of an inch, to obtain a package profile.
The alignment offset will be calculated with this profile.
Learning the length of the package at the alignment offset.
The dimensions of a package must take into account the leads if leads are present. These values in conjunction with the set tolerance will provide the system the ability to determine if the package has a bent lead.