WORKING APPARATUS AND WORKING METHOD FOR CIRCUIT BOARD

• US 20090125141A1
• Filed: 11/24/2006
• Published: 05/14/2009
• Est. Priority Date: 11/29/2005
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Nagao, Kazuhide, Okuda, Osamu, Noda, Takahiro, Endo, Tadashi
• Granted Patent: US 7,809,461 B2
• Time in Patent Office: Days
• US Class Current: 700/121
• CPC Class Codes: H05K 13/0812 the monitoring devices being integrated in the mounting machine, e.g. for monitoring components, leads, component placement
• CPC Class Codes: H05K 13/0815 Controlling of component placement on the substrate during or after manufacturing
• CPC Class Codes: Y10T 29/53091 for work-holder for assembly or disassembly
• CPC Class Codes: Y10T 29/53178 Chip component
• CPC Class Codes: Y10T 29/53261 Means to align and advance work part

Abstract

In estimating a curved surface model by approximating the shape of the board surface of a circuit board, auxiliary measurement spots are set other than measurement spots on the board surface, eligibility as a sampling displacement magnitude in estimating a curved surface model is determined according to a difference in a displacement magnitude from a work reference surface. When the sampling displacement magnitude is determined to be ineligible, a new measurement spot is reset. By this operation, a local increase and decrease in the displacement magnitude due to a discontinuity of the board surface exerts no influence on the estimation of the curved surface model, and the curved surface model approximated more closely to the shape of the actual board surface is estimated, leading to an improvement in the work quality with the working height adjusted to the proper height.

Claims

1. A working apparatus for a circuit board, the apparatus comprising:

a measuring means for measuring a displacement magnitude of the circuit board from a work reference surface regarding at least three measurement spots set on a working surface of the circuit board and a plurality of auxiliary measurement spots whose at least one is set in the neighborhood of each of the measurement spots;

an operation means for determining whether a difference between a maximum value and a minimum value of the measurement displacement magnitudes from the work reference surface measured by the measuring means at the measurement spots and the auxiliary measurement spots set in the neighborhood of the measurement spot is not greater than a threshold value, estimating a shape of the working surface of the circuit board by a curved surface model on the basis of the measurement displacement magnitude of each of the measurement spots determined to be not greater than the threshold value and calculating an operation displacement magnitude of the curved surface model from the work reference surface; and

a correcting means for correcting a working height in performing works on the working surface of the circuit board on the basis of the operation displacement magnitude of the curved surface model calculated by the operation means.

2. The working apparatus for a circuit board as defined in claim 1, further comprising:

an adaptability determining means for comparing the operation displacement magnitude at each of the measurement spots of the curved surface model calculated by the operation means with the measurement displacement magnitudes at each of the measurement spots to determine whether a difference between both of the displacement magnitudes is not greater than a threshold value and determining that the curved surface model is adapted upon determining that the difference is not greater than the threshold value.

3. The working apparatus for a circuit board as defined in claim 1, wherein

the operation means estimates, for each of a plurality of compartment working surfaces obtained by comparting the working surface of the circuit board into a plurality of regions, a shape of the compartment working surface by the curved surface model on the basis of the measurement displacement magnitude.

4. A working method for a circuit board, the method comprising:

setting at least three measurement spots on a working surface of the circuit board;

measuring a measurement displacement magnitude from a work reference surface of the circuit board at each of the set measurement spots;

determining whether the measurement displacement magnitude at the measured measurement spot is eligible as a sampling displacement magnitude;

setting upon determination of ineligibility a new measurement spot in place of the measurement spot that has been determined to be ineligible and measuring the measurement displacement magnitude to determine eligibility of the new measurement displacement magnitude, or estimating upon determination of eligibility a shape of the working surface of the circuit board by a curved surface model on the basis of the measurement displacement magnitude at the measurement spot and calculating an operation displacement magnitude of the curved surface model from the work reference surface; and

performing works on the circuit board by correcting a working height in performing works on the working surface of the circuit board on the basis of the calculated operation displacement magnitude of the curved surface model.

5. The working method for a circuit board as defined in claim 4, wherein

at least one auxiliary measurement spot is set in the neighborhood of each of the measurement spots in setting the measurement spots,

the measurement displacement magnitude of each auxiliary measurement spot is measured in measuring the measurement displacement magnitude, and

it is determined that the displacement magnitude is eligible in determining the eligibility of the displacement magnitude when a difference between a maximum value and a minimum value of the measurement displacement magnitudes of the measurement spots and the auxiliary measurement spots set in the neighborhood of the measurement spots at each of the measurement spots is not greater than a threshold value.

6. The working method for a circuit board as defined in claim 4, wherein

it is determined, after the curved surface model is estimated, whether the estimated curved surface model is adapted to the working surface of the circuit board, and

when the curved surface model is determined to be not adapted, a new curved surface model is estimated by additionally setting a new measurement spot in setting the measurement spot.

7. The working method for a circuit board as defined in claim 6, wherein,

in determining the adaptability of the estimated curved surface model to the working surface of the circuit board, the operation displacement magnitude at each of the measurement spots of the curved surface model is compared with the measurement displacement magnitude at each of the measurement spots, and it is determined that the curved surface model is adapted by a fact that a difference between both of the displacement magnitudes is not greater than a threshold value.

8. The working method for a circuit board as defined in claim 4, wherein

in estimating the curved surface model, a shape of a compartment working surface is estimated by the curved surface model on the basis of the measurement displacement magnitude for each compartment working surface obtained by comparting the working surface of the circuit board into a plurality of regions.