JPH04301814A - Press device for liquid crystal panel production - Google Patents

Abstract

PURPOSE:To adjust the parallelism between a pressure applying plate and a pressure receiving plate with a high precision by providing the pressure plate above a pressure transmission plate with an inclination correcting mechanism, which can be minutely moved back and forth and is supported at three points, between them. CONSTITUTION:A servo motor 9 is operated to bring a pressure applying plate 5A into contact with a plate 4A with a press shaft 13 between them, and this operation is stopped when a load cell 20A reaches a prescribed pressure value for calibration. Pressure values of load cells 20B and 20C at this time are converted to electric signals and are transmitted to a microcomputer 24 as the controller. When load cells 20A to 20C have the same pressure value, nothing is done; but when they are different from one another, required voltages are applied to piezoelectric elements 23B and 23C through electrodes 21B, 22B, 21C, and 22C. Pressure values of three load cells 20A to 20C are corrected to the same value to obtain the parallelism between the pressure applying plate 5A and the pressure receiving plate 4A.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a press apparatus for manufacturing a liquid crystal panel in which empty cells are assembled by sealing the periphery of two glass substrates, upper and lower, provided with transparent electrodes with a predetermined gap between them.

0002

[Prior art and problems] Conventionally, in the liquid crystal panel manufactured as described above, if the gap between the glass substrates is uneven, color unevenness will occur in the liquid crystal panel, so it is necessary to make the gap amount uniform over the entire surface of the glass substrate. be. Various methods have been proposed to solve this problem, and most of them have been able to achieve the objective. On the other hand, since glass substrates are very thin, clear display cannot be achieved unless they are pressed uniformly, and expensive glass substrates with transparent electrodes must be discarded, making it desirable to improve yields. However, to solve this problem, there is a problem not only with the glass substrate but also with the parallelism of the pressure plate and the pressure receiving plate of the press device, so that a sufficient solution has not been realized.

0003

[Purpose] The present invention has been made in view of the above, and an object thereof is to provide a press device that can accurately adjust the parallelism of a pressure plate and a pressure receiving plate when pressing two glass substrates for a liquid crystal panel. It is something to do.

0004

[Means for Solving the Problem] In order to achieve the above-mentioned object, the press device for manufacturing liquid crystal panels in the present invention has a press drive mechanism configured with an electric servo motor that generates a press force, and presses the press via a ball screw mechanism. The shafts are connected to be movable up and down, and a pressure transmission plate is provided at the upper end of the press shaft, and the pressure transmission is fitted to an erected column via a sleeve so as to be movable up and down, and a pressure transmission plate is attached to the upper part of the pressure transmission plate. A movable plate is provided via an inclination correction mechanism, and as the inclination correction mechanism, three load cells are arranged in a triangular shape when viewed from the top, and a piezoelectric element that makes minute reciprocating movement with electrodes attached to the upper and lower surfaces is attached to the top of each load cell. A pressure plate with a built-in heater is attached to the upper part of the movable plate, and above the pressure plate,
A fixed plate with a pressure receiving plate with a built-in heater attached to the bottom is installed.
The electric servo motor and each load cell, and each load cell and each piezoelectric element are electrically connected via a controller including a microcomputer.

[0005]

[Embodiments] Examples will be explained in detail below based on the drawings. A foundation plate 2 is fixed to the upper part of the ceiling of the gate-shaped foundation 1, and pillars 3, 3 are screwed and erected at the four corners of the foundation board 2, and at the upper ends of the pillars 3, 3. A fixing plate 4 having a pressure receiving plate 4A attached to its lower surface is screwed and fixed. Further, a pressure transmission plate 19 is fitted to the columns 3, 3 via sleeves 6, 6 so as to be movable up and down.
At the top, a movable plate 5 having a pressure plate 5A fixed to its upper surface is connected via a tilt correction mechanism R. A mounting plate 7 is fixed to the top of the base plate 2, and a housing 8 having a convex cross section is fixed to the mounting plate 7 by penetrating it from above and below. A downward electric servo motor 9 is attached to the upper right side of the convex housing 8, and its rotating shaft 10 protrudes into the housing 8 and has a gear 11 at its tip.
is fixed. Further, a press shaft 13 is disposed at the protrusion position of the housing 8, the base of which has a ball nut 12 structure, and which protrudes freely through the housing 8 and moves up and down along the inner surface of the housing 8. A ball screw 15 vertically supported within the housing 8 is screwed into the ball nut 12 of the press shaft 13 via a bearing 14 . A gear 16 is fixed to the lower end of the ball screw 15, and a timing belt 17 is wound between it and the gear 11. Furthermore, the pressure transmission plate 19 is attached to the upper end of the press shaft 13 via a bracket 18.
is fixed horizontally.

Now, to explain the tilt correction mechanism R, 3
Load cells 20A, 20B, and 20C are arranged on the pressure transmission plate 19 in the shape of an equilateral triangle when viewed from above, and electrodes 21A, 22A, 21B, and 22C are attached to the upper and lower surfaces of the load cells 20A, 20B, and 20C. Moreover, cylindrical and laminated piezoelectric elements 23A and 23B
, 23C are attached, and the movable plate 5 is attached on the upper electrodes 21A, 21B and 21C.

Further, the electric servo motor 9 is electrically connected to a controller consisting of the load cells 20A, 20B, 20C and a microcomputer 24, and each load cell 20A, 20B, 20C is connected to the piezoelectric element 23A. , 23B, 23C and the microcomputer 2
They are electrically connected via 4. With such an electrical connection, the servo motor 9 connects the pressure plate 5A and the pressure receiving plate 4.
When checking and correcting the parallelism of A, load cell 20
It is controlled by the microcomputer 24 to temporarily stop Sado when receiving a signal that A has reached a predetermined calibration pressure value, and the total pressure of each load cell 20A, 20B, and 20C is a predetermined value when pressurizing the glass substrate. It is controlled by the microcomputer 24 to continue operating until reaching .

In addition, the piezoelectric elements 23A, 23B, and 23C are connected to other load cells 20B and 23C when the load cell 20A reaches a predetermined calibration pressure value when confirming and correcting the parallelism between the pressure plate 5A and the pressure receiving plate 4A. A voltage with a potential difference of 0 to 150V is applied to the other load cells 20B and 20C via a step-up transformer (not shown) through the electrodes 21B, 22B, 21C, and 22C so that the pressure of 20C is equal to the other load cells 20B and 20C, and a maximum range of 16μ is applied to one cell. It is controlled by a microcomputer 24 so as to perform minute driving with a force of less than 800 kgf per hit. Further, the pressure receiving plate 4A and the pressure plate 5A are made of alumina and have a built-in heater.

[0009] In the apparatus constructed as described above, the following operation is first performed to confirm and correct the parallelism between the pressure plate 5A and the pressure receiving plate 4A. That is, in the state shown in FIG. 1, the servo motor 9 is operated to bring the pressure plate 5A into contact with the pressure receiving plate 4A via the press shaft 13, and when the load cell 20A reaches a predetermined calibration pressure value, its operation is stopped. Ru. At this time, the pressure values of the load cells 20B, 20C are converted into electrical signals and transmitted to the microcomputer 24. If the pressure values of the load cells 20A, 20B, 20C are the same, the pressure values are left as they are; if they are different, the pressure values of the electrodes 21B, 22B, 21C,
Three load cells 20A, 20B,
The pressure value of 20C is corrected to the same value to obtain parallelism between the pressure plate 5A and the pressure receiving plate 4A. Since the movable plate 5 is mounted on the pressure transmission plate 19 via the tilt correction mechanism R supported at three points, the parallelism obtained in this way is achieved by making the pressure values of the three points coincide, so that the parallelism becomes flat in space. By specifying this, accurate parallelism can be obtained and the inclination can be corrected.

Next, while maintaining the corrected inclination of the pressure plate 5A, the servo motor 9 is operated in reverse to return the pressure plate 5A to its original position together with the movable plate 5.
A sheet of glass substrate is placed with its peripheral opposing surface sealed with a sealant. Next, the pressure receiving plate 4A and the pressure plate 5
Electric current is applied to a heater (not shown) built in A to heat the pressure receiving plate 4A and the pressure plate 5A to a predetermined temperature, and the servo motor 19 is operated to heat the two glass substrates to the pressure receiving plate via the pressure plate 5A. 4A for a predetermined period of time while maintaining parallelism at a predetermined pressure. In this way, the two glass substrates are heated and pressurized at a predetermined temperature for a predetermined period of time, whereby the sealing agent is heated and softened and then hardened, and an empty cell for a liquid crystal panel is obtained.

[0011] The total pressure at this time is the load cells 20A, 20
It is expressed as the sum of three B, 20C and monitored on a CRT together with the pressure per unit area divided by the area of the glass substrate. Further, the time and pressure during this time are monitored and stored in an external storage device, and feedback control is performed, so that from the second time onwards, the pressure pattern that has been stored is mainly followed. In the above embodiment, a case of a set of two glass substrates has been described, but it can also be used when manufacturing a liquid crystal panel by laminating multiple sets of glass substrates.

0012

Effects of the Invention As is clear from the above description, the present invention corrects the inclination between the pressure plate and the pressure receiving plate by using a three-point support inclination correction mechanism that is capable of minute reciprocating movement, and after making them parallel, the glass substrate is removed. Since empty cells for liquid crystal panels are obtained by heating and pressurizing the cells, empty cells for liquid crystal panels with uniform gaps can be manufactured at a high yield, which has a significant effect on this industry.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view showing an embodiment of the present invention.

[Explanation of symbols]

4A Pressure receiving plate 5A Pressure plate 9 Servo motor 12 Ball nut 13 Press shaft 15 Ball screw 19 Pressure transmission plate 20A 20B 20C Load cell 21A
22A 21B 22B 21C 22C
Electrode 23A 23B 23C Piezoelectric element 24
Controller R Tilt correction mechanism

Claims (1)

[Claims] Claim 1: A press shaft is vertically movably connected to a press drive mechanism composed of an electric servo motor and generates a press force via a ball screw mechanism, and a pressure transmission plate is provided at the upper end of the press shaft. , a movable plate is fitted to the upright pillar for pressure transmission via a sleeve so as to be movable up and down, and a movable plate is provided on the upper part of the pressure transmission plate via an inclination correction mechanism, and three load cells are arranged on a flat surface as the inclination correction mechanism. The structure is arranged in a triangular shape when viewed from above, and a piezoelectric element with electrodes attached to the upper and lower surfaces and capable of minute reciprocating movement is attached to the top of each load cell.A pressure plate with a built-in heater is attached to the top of the movable plate, and the pressure plate A fixed plate having a pressure receiving plate with a built-in heater attached to the lower surface is disposed above, and the electric servo motor and each load cell, and each load cell and each piezoelectric element are electrically connected via a controller consisting of a microcomputer. Press equipment for manufacturing LCD panels characterized by: