SU1066051A1 - Device for inspecting printed circuit boards - Google Patents

Abstract

A DEVICE FOR THE CONTROL OF THE PERSONAL BOARDS, containing a contact bar formed by single contact groups consisting of contacts arranged in series along one of the axes of the coordinate grid at its nodes with variable pitch and evenly spaced along another axis of the coordinate grid, characterized in that in order to increase the degree of unification and reduce the dimensions of the contact field, single contact groups are arranged along one of the axes of the coordinate grid with displacement one relative to another, the value which in the steps of the grid is determined from the relation C A, @ Au. (L where n is the number of contacts in the group Ai2 is the number j multiple of the height of the height n (n-1) +1. O5 o cd

Description

This invention relates to automation technology and can be used to automatically control electrical parameters of printed circuit boards.

A device for controlling electrical parameters of printed circuit boards is known, comprising a base, a contactless unit with a movably positioned (shmi on the basis of test pins, a pressing mechanism with a pneumatic drive, a two-coordinate programmable-controlled stepper drive and a measuring unit connected to the contacting unit. Contact elements of the contact unit The unit is fed parallel to the plane of the board to be attached using a powered cartridge mounted on a two-axis drive f and.

The disadvantages of this device are the complexity of the design due to the need to restructure the contact block, as well as the large displacement required to complete the inspection of printed circuit boards with tight pattern placement, which leads to an increase in control time and a decrease in the reliability of conductors.

Closest to the proposed technical entity is a device for controlling printed circuit boards, containing a contact field formed by single contact groups consisting of contacts arranged successively along one of the axes of the coordinate grid at its nodes with variable pitch and evenly spaced along the other axis coordinate grid C 21.

The disadvantages of the known device are its large size, uneven clamping and a relatively large amount of switching equipment. The contact block is made longer than the tested board on a single spacing of the location of the contact elements, which leads to a significant increase in the dimensions of the contact block when it is necessary to monitor large size boards. In addition, such an arrangement of contact elements leads to a limitation of the control of small-size boards due to large gaps between the rows of contact elements. one.

The purpose of the invention is to increase the degree of unification and reduce the size of the contact floor.

This goal is achieved by the fact that in the device for control of printed circuit boards, containing a contact field formed by single contact groups consisting of contacts arranged in series along one of the axes of the coordinate grid at its nodes with variable pitch and evenly spaced

along the other axis of the coordinate grid, single contact groups are located along one of the axes of the coordinate grid with displacement one relative to the other, the value of which in the steps of the coordinate grid is determined from the relation

2iS: lI ± -1

f

AZ

where n is the number of contacts in the group; Aj. is a multiple of the expression psp-1) +1. FIG. 1 depicts the proposed

- device, about & (i.vid. in Fig. 2 view A in Fig. 1; in Fig. 3 - spring-loaded contact elements; in Fig. 4 - execution of a contact field for five contacts in the contact group in the prototype and the proposed device, respectively displaced one relative to another.

The device contains a base 1,

on which the two-coordinate movement mechanism 2 and the mechanism 3 of the pressing of the printed circuit board 4 are fixed, the contact unit 5, which is hinged to the base 1, and the measurement unit 6 connected to the contact unit 5 via the switch 7.

0 Contact block 5 is designed as a set of single contact groups,

united in a ruler 8. placed with an offset along one of the axes of the coordinate set one relative to

5 another. Spring-loaded contact elements 9 are located in the dielectric sockets to form group 10.

The clamping mechanism 3 provides the clamp of the checked board 4 about the contact elements 9 for the time of the next test cycle and for its removal from the contacts for the time of the movement.

The device works in the following way.

The test cycle starts from pressing the board 4 to the contact elements 9. The required electrical parameters are checked between those points of the board 4 to which the contact elements 9 are connected, then the board is retracted from the contact unit 5 and the movement mechanism 2 moves the presser mechanism 3 with the board 4 by one step along the direction of movement, and the cycle is repeated. In each test cycle, the control unit and the measurement unit B compares the measured parameters with the set ones and the results of the comparison of the coordinates of the defective circuits or the state of the parameter Pass - reject are remembered. A check of all pairwise combinations of points of the printed circuit board 4 ensures, when moving it along two co-ordinates: along the axis of AI on five axes, and along the other on A steps. The pressing mechanism 3 with the board 4 returns to its original position and after installing the next board, the device GOTO110 to a new check. Information about the results of the inspection of the circuit board C oordnaty defective circuits or the condition of the parr meter fit, if

No defects were detected with npoBepKeji displayed using alpha-cipher printing. Enter the scan program

It is possible both from a punched tape and from this floor in the mode of CC1 software. The application of the proposed device allows checking the electrical parameters of any standard sizes of printed circuit boards without rebuilding the contact block with a significant reduction in the volume of the wipers and overall dimensions of the device . The specified location of the contact elements improves the manufacturability of the contact block:

0 ka, facilitates the diagnosis of defective places on the groove and improves operational characteristics (maintainability).

Wi A

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J / K KOMMi / mamopi /

Fig.z

A B C

FIG. C

Claims (1)

DEVICE FOR MONITORING PERSONAL CIRCUIT BOARDS, containing a contact field formed by single contact groups consisting of contacts arranged sequentially along one of the axes of the coordinate grid at its nodes with a variable pitch and uniformly located along the other axis of the coordinate grid, characterized in that, with In order to increase the degree of unification and reduce the dimensions of the contact field, single contact groups are located along one of the axes of the coordinate grid with an offset of one relative to the other, the value of which in steps of the coordinate grid is determined from the relation „n (n-1) +1 o _Λή ---------—> g _ Ar. where η is the number of contacts in the group; A <2 ~ is a multiple of the value of the expression n (n-1) +1.