00197787-02_SI_SIPLACE_HeadVerification_EN - 第71页

6 Description of the test results 6.18 Nozzle spring Software Manual SIPLACE Head Verification 03/2018 71 6.18.3 Interpretation of the results obtained ‘Nozzle spring’ / ‘Signal threshold’ error for all segments Cause So…

6 Description of the test results

6.18 Nozzle spring

70 Software Manual SIPLACE Head Verification 03/2018

6.18 Nozzle spring

6.18.1 Measurement principle

The Nozzle spring measurement checks the state of the spring with respect to its deflection, brit-

tleness and the switching (signal) threshold at the Z-axis down light barrier.

Before the measurement starts, a head reference run is carried out during which all nozzles are

pressed onto the DP at the nozzle station to ensure a firm fitting. During the measurement itself,

every segment is moved down and back up again using different travel profiles to measure the pos-

itions at which the end signal is triggered.

●

The nozzle spring is verified by comparing the positions at which the end signal is triggered,

moving the segment down first with low force and the current sensor mode (Z-Low Force), fol-

lowed by high force and light barrier mode (Z-High Force).

●

The threshold value is verified by comparing the position at which the end signal is triggered,

moving the segment down with standard force and light barrier mode (Z-Light Barrier), with

the position determined for the low force movement (Z-Low Force).

6.18.2 Measurement result

Fig.52: Result view – Nozzle spring measurement

1 Measured Segment

2 Calculated value for the spring that has been compressed completely:

Nozzlespring = Z-HighForce – Z-LowForce

3 Calculated value for the distance until the Z-axis down light barrier is triggered.

Signal threshold = Z-Light Barrier - Z-Low Force

4 Result view indicating if the values are within (green tick) or outside (red cross) the limits.

5 Graph showing the Nozzle spring values for each segment.

6 Graph showing the Signal threshold values for each segment.

6 Description of the test results

6.18 Nozzle spring

Software Manual SIPLACE Head Verification 03/2018 71

6.18.3 Interpretation of the results obtained

‘Nozzle spring’ / ‘Signal threshold’ error for all segments

Cause Solution

Light barrier Z-down defective ► Check the Z-axis down light barrier and re-

place it if necessary.

‘Nozzle spring’ / ‘Signal threshold’ error for individual segments

Cause Solution

Segment spring is bent or mechanically dam-

aged.

► Replace the DP.

The position, fixture or state of the cover switch-

ing ring is faulty.

► Check the fixture and, if necessary, re-

place the cover switching ring.

Spring pin at back of DP lock damaged. ► Replace the head.

6 Description of the test results

6.19 Segment offset up & down (fast)

72 Software Manual SIPLACE Head Verification 03/2018

6.19 Segment offset up & down (fast)

6.19.1 Measurement principle

Segment offset up & down (fast) is a quick measurement to determine the eccentricity of a seg-

ment to the center of the component camera.

●

Segment offset up is the offset of the segment center in the up position to the center of the

component camera.

●

Segment offset down is the offset of the segment center in the bottom position to the center

of the component camera, either for the pick-up or placement of components. It is also known

as the offset between the PCB camera center and the center of the component camera.

During the measurement, the PCB camera measures the initial position of the calibration tool (CT)

in the calibration tool pocket. The CT is picked up by each segment which is turned to 0° and

moved to the component camera, where the CT is measured (optically centered) again. The de-

termined offset values are then used to calculate the CT position. Afterwards, the CT is placed

back into the calibration tool pocket where it is measured another time by the PCB camera. The de-

termined offset values are then used to calculate the CT position.

NOTICE

Termination of test sequence

If a measurement shows a segment outside the allowed limits, all subsequent measure-

ments will be terminated. It is assumed that the segment is seriously deformed and that the

head is no longer able to perform.

► Replace the segment immediately before performing other measurements.