KR100340188B1 - Panel feeding mechanism to compensate the Abbe's Offset along the linear guide way - Google Patents

Abstract

The present invention is a transport mechanism for correcting the Abbe's offset of the guideway used in the device for inspecting the panel formed with the electrode pattern, the carrier supported by the guide block to have a rotational compliance (only) in the horizontal direction only (carrier) Bed; A guideway for guiding the guide block; A transfer ball nut supported and supported by a leaf spring such that the carrier bed is only capable of horizontal displacement in the horizontal direction; A ball screw and a servo motor for rotationally driving the transfer ball nut; And it is configured to include a control unit for determining and controlling the moving distance of the carrier bed in conjunction with the rotation of the servo motor, even if the straightness of the guideway is poor feeding error due to the Abbe's offSet of the guideway (Feeding error) As a result, the inspection accuracy of the electrode pattern formed on the panel can be improved, and the manufacturing cost of the product can be reduced.

Description

Panel feeding mechanism to compensate the Abbe's Offset along the linear guide way}

The present invention relates to a panel transport mechanism for use in a device for inspecting the electrical properties (open / short) of the electrode pattern formed in a panel-like product, such as plasma display panels (PDP). In order to inspect the electrical characteristics of the electrode pattern formed on the panel by a scanning method, as shown in Figure 1, the inspection device such as a rolling wire probe 110 or a capacitive proximity sensor probe 120 as the inventor separately filed To be fixed at a predetermined position on the panel 10 and the PDP panel to be inspected is moved along the guideway, or on the contrary, the inspection apparatus is moved while the panel to be inspected is fixed to scan the electrode pattern 101.

In general, however, PDP panels are not only large (1 meter long for 42 inches wide). When the straightness is poor due to the Abbe's Offset phenomenon of the guide way, a feeding error occurs and the inspection precision is reduced. In order to secure the inspection accuracy, the straightness of the guideway should be kept below the line width of the electrode pattern, but the manufacture of such a guideway requires a high degree of precision processing, resulting in an increase in product cost.

Therefore, the present invention enables to compensate the feeding error of the guideway even without high-cost precision processing to increase the straightness of the guideway, thereby reducing the burden of product manufacturing cost and ensuring inspection accuracy. It is a technical problem to propose a transport mechanism for panels.

FIG. 1 schematically illustrates an inspection method for scanning an electrode pattern formed on a PDP.

FIG. 2 illustrates the exaggerated feeding error generated when there is an error in the straightness of the guide way for guiding the conveyed panel.

3A and 3B show examples of kinematic structural diagrams in which the carrier bed is rotated and displaced only in the horizontal direction.

4 is an exaggerated state in which the Abe offset in the guideway is corrected during the movement by the ball nut and the ball screw in the case of the same mechanism as that of FIG. 3B.

FIG. 5 is an exemplary view specifically illustrating a transfer mechanism of the present invention corresponding to the mechanism structure of FIG. 3B.

6 is an overall block diagram of a scan type inspection system including the transfer mechanism of the present invention as a reference.

* Description of the symbols for the main parts of the drawings *

10 panel 100 carrier bed

130: guideway 140: guide block

220: servomotor 222: ball screw

225: ball nut 226: leaf spring

The present invention for achieving the above object is a carrier bed support-connected to the guide block to have a rotational compliance (Compliamce) only in the horizontal direction; A guideway for guiding the guide block; A transfer ball nut supported and supported only by the carrier bed in a horizontal direction; A ball screw and a servomotor for rotationally driving the transfer ball nut; And characterized in that it comprises a control unit for determining and controlling the moving distance of the carrier bed in conjunction with the rotation of the servomotor.

Prior to explaining the transfer mechanism of the present invention, the entire system for inspecting the electrode pattern formed on the panel by the scanning method will be described with reference to the block diagram of FIG. The control unit 20 for controlling the operation of the entire system, the input unit 21 for inputting a command to the control unit 20, consisting of a touch panel, a keyboard or a mouse, and the control of the control unit 20 The ball screw which moves the panel mounting part 223 by the linear scale 221 in conjunction with the rotation of the servo motor 220, the panel mounting part 223 in which the panel to be scanned is mounted, and the rotation of the servomotor 220 is carried out. Servo mechanism unit 22, consisting of a TFT, LCD, etc., a display unit 23 for displaying the operation state of the inspection apparatus and the like under the control of the control unit 20, and the control unit 20 A bus module 24 providing an interface between the external device and an external device, and a sensing module for detecting an electrical state of an electrode pattern and supplying sensing data to the control unit 20 under the control of the control unit 20. It consists of 25.

The servo mechanism unit 22 includes a servo motor 220 driven under the control of the controller 20, a panel mounting unit 223 on which a panel to be scanned is mounted, and a panel mounting unit 223 in conjunction with rotation of the servo motor. It consists of a ball screw 222 to move a distance determined by the linear scale 221.

The sensing module 25 includes a vision module 250 for detecting whether the left / right input position of the electrode pattern is on the same line, a rolling wire module 251 for scanning the electrode pattern while rotating the wire, and a non-contact type. The capacitive proximity sensor module 252 for scanning the electrode pattern and a sequence sensor module 253 for detecting whether the transfer position of the glass panel is out of a certain range.

Here, the vision module 250 includes a CCD camera, a zooming lens, a loading / unloading actuator, and an aerostatic pad for discharging air of a predetermined pressure.

The rolling wire module 251 rotates at a constant speed while the rolling wire probe is brought into contact with the electrode pattern, a compact servo motor for rotating the rolling wire probe, an encoder for detecting the speed of the servo motor, It consists of a loading / unloading actuator and an air pressure pad.

The capacitive proximity sensor module 252 includes a non-contact capacitive proximity sensor probe, a loading / unloading actuator, and an air pressure pad, which inspect the electrical characteristics of the electrode pattern by using the capacitance of the electrode pattern.

The sequence sensor module 253 is composed of a glass detection switch, a servo limit switch, and a zero position switch.

The present invention relates to a transfer mechanism belonging to the servo mechanism portion 22 in the overall system as described above.

Then, the feeding error that may occur in the guideway of the transfer mechanism of the present invention will be described kinematically with reference to FIG.

That is, in FIG. 2, the straightness of the guideway 130 is extremely exaggerated (actually having a fine curvature), and the guide which must move straight in the direction of the arrow by the driving means (not shown). As the block 140 moves along the curved guideway 130, the carrier bed 100 fixed to the guide block 140 also rotates in a horizontal direction along the guideway 130, thereby showing a feeding error ( Feeding error) This feeding error is a scanning position of an inspection apparatus such as a rolling wire probe or a capacitive proximity sensor probe fixed at a predetermined position corresponding to the horizontally disposed electrode pattern placed on the carrier bed 100. This results in a misalignment with the result that the inspection accuracy cannot be maintained.

Therefore, in the present invention, a kinematic structure capable of absorbing feeding errors due to the rotational displacement as described above has been devised.

That is, in FIG. 3A, four guide blocks 140 moving along two parallel guideways 130 are installed on each guideway, and four leaf springs 141 are provided on the four guide blocks 140, respectively. ) Is guided so that the guide block and the carrier bed 100 are firmly fixed in the x, y, and z axis directions and rotate only in the rotational direction (horizontal direction), by being connected so as to meet in a diagonal direction at the virtual center in the carrier bed 100. It is configured to have compliance.

In addition, the mechanical diagram of Figure 3b is also by fastening the guide block 140 and the carrier bed 100 guided to the guide bar 130, another modified embodiment of Figure 3a by the rotary hinge 142 is equipped with a torsion spring The carrier bed 100 was configured to have rotational compliance only in the rotational direction.

The mechanical structure as described above means that the carrier bed 100 is free from the rotational displacement of the guide block 140 guided along the guideway 130, which means that if the carrier bed 100 is moved separately, Fixed by the propellant, when moving straight in a constant posture, for example, as shown in the middle portion of FIG. 2, even if the straightness of the guideway 130, even if the curvature is curved along the curved guideway Apart from the guide block rotating in the direction, the carrier bed will be able to maintain the posture, and will eventually be able to go straight absorbing the feeding error of the guideway.

Figure 4 shows the structure of the mechanism that can maintain the straightness by absorbing this even if a feeding error occurs because the straightness of the guideway is poor as described above.

That is, in FIG. 4, the carrier bed 100 is moved on the ball screw 222 and the ball screw 222 which are rotated by the rotation of the servo motor 220 and the servo motor 220 separately from the curved guide way 130. Both ends of the carrier bed 100 are connected by a ball nut 225 and a leaf spring 226, respectively. Therefore, when the two servomotors 220 rotate at the same speed, they are interlocked with each other and the two ball nuts 225 along the ball screw axis also move linearly by the same distance and are connected to the plate spring 226 by the carrier bed 100. Also, the carrier bed moves along the same distance. At this time, the carrier bed moves along the curved guideway, but is connected to the guide block 140 so as to have rotational compliance only in the rotational direction. It will move straight without losing attitude. Here, the carrier bed 100 and the ball nut 225 are connected to each of the leaf springs 226 as described above, which are axial directions of the curved guideway 130 and the ball screw 222 as shown. This is to displace the carrier bed 100 in the left and right directions by the deviation while absorbing the mechanical force of the connection portion due to the deviation in the left and right directions due to the mismatch.

Therefore, according to the mechanism of the present invention, the carrier bed 100 absorbs the feeding error in spite of the poor straightness of the guideway 130, but moves straight forward while inevitably moving the carrier bed 100 to the ball screw 222. There is no choice but to move left and right by the deviation shown in the axial direction. However, the straightness of the actual guideway is not only fine as shown in the drawing (exaggerated), but also a linear pattern in which the electrode pattern to be inspected is orthogonal to the scanning direction. The inspection objective can be achieved without being affected by (displacement).

Figure 5 shows an embodiment of the panel transfer mechanism of the present invention embodying this based on the mechanism structure as described above.

That is, two servo motors 220 and 220, ball screws 222 and 222 linked by rotation of the servo motors, ball nuts 225 pivoting along the ball screws, and the ball nut. The carrier bed 100 connected through the leaf springs 226 and 226, the guide blocks 140 and 140 connected to the carrier bed, and the carrier block and the guide block are provided only in the rotational direction. A panel feed mechanism comprising four leaf springs 141 connected to each other, and guide ways 130 and 130 for guiding the guide block, wherein reference numeral 223 denotes a rotary table, and 223a denotes an intake hole of a double chuck, 223b. The vent hole of the air pressure pad, 224 is a coupling, 250 is a camera, 110 is a rolling wire probe, 120 is a capacitive proximity sensor probe.

As described above, the present invention absorbs the feeding error caused by the poor straightness of the guideway in the device for inspecting the electrode pattern by the carrier bed provided to have compliance only in the rotational direction, Since the ball nut driven by the motor is fixedly connected to the carrier bed by the leaf spring, the abe offset of the guideway can be corrected, so that it is necessary to use a high cost and precision processing to maintain the straightness of the guideway. As a result, the reduction of product cost was realized.

Claims (5)

An apparatus for inspecting a panel on which an electrode pattern is formed, comprising: a carrier bed supported connected to a guide block to have only rotational compliance in a horizontal direction; A guideway for guiding the guide block; A transfer ball nut supported and supported such that the carrier bed is only capable of horizontal displacement in the horizontal direction; A ball screw and a servo motor for rotating the transfer ball nut; And a control unit for determining and controlling the moving distance of the carrier bed in association with the rotation of the servomotor. According to claim 1, wherein the carrier bed and the guide block are arranged so that each of the four leaf springs upright to have a vertical rigidity, wherein the virtual extension of each of the leaf springs cross each other at a virtual center point in the carrier bed in a diagonal direction. Therefore, the panel transport mechanism capable of correcting the Abe offset of the guideway, characterized in that the carrier bed is configured to have only rotational compliance in the horizontal direction. The guideway of claim 1, wherein the carrier bed is configured to have only rotational compliance in a horizontal direction by fastening the carrier bed and the guide block with a rotary hinge equipped with a torsion spring. Panel transfer mechanism The carrier bed of claim 1, wherein the carrier bed is fixedly connected to the ball nut by two leaf springs, but the leaf springs are erected so as to have rigidity in the vertical direction, so that the carrier bed is capable of only horizontal displacement in the horizontal direction. Panel transfer mechanism that can correct the Abe offset of the guideway The apparatus of claim 1, wherein the inspection apparatus for scanning the panel on which the electrode pattern is formed is a rolling wire probe, a capacitive proximity sensor probe, or a combination thereof.