JP3453316B2 - Liquid crystal pressure supply device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal pressure supply device for injecting liquid crystal liquid into a liquid crystal display device.

[0002]

2. Description of the Related Art A liquid crystal panel, which is generally a liquid crystal display device, is constructed as shown in FIG. 7 (plan view) and FIG. 8 (enlarged sectional view of an X portion in FIG. 7). It has a structure in which the sealing material 51 is applied to and bonded to each other. In addition, micro beads 52 are arranged between the two pieces of glass so that the gap (distance between the glasses) of the liquid crystal panel is kept constant. This space 53
The liquid crystal liquid is filled in the liquid crystal display device.

The injection of the liquid crystal liquid into the liquid crystal panel is performed by an injection port 54 and an exhaust port 55 provided in the liquid crystal panel (shown in FIG. 7).
Is performed using. In the liquid crystal panel shown in FIG. 7, only one injection port 54 for injecting the liquid crystal liquid is provided at the center of one side, and one exhaust port 55 for evacuating the internal space is provided at each end of the opposite side. It is a structure.

Before injecting the liquid crystal liquid, a defoaming process is performed to degas the gas dissolved in the liquid crystal liquid. The defoamed liquid crystal liquid is injected into the liquid crystal panel without contacting with a gas such as air.

FIG. 5 shows an example of a conventional liquid crystal injection device.
The liquid crystal panel 13 has an injection port for injecting the liquid crystal liquid and an exhaust port for exhausting the gas inside, and an injection connector 11,
An exhaust connector 14 is attached and connected to each device. The degassed liquid crystal liquid 1 is stored in a bellows-like liquid crystal container 2 that expands and contracts, and the injection valve 9 and the liquid crystal container exhaust valve 19 are closed so that the liquid crystal liquid 1 is stored in a state where it does not come into contact with gas such as air. .

In the injection step, the exhaust side atmosphere valve 16 is closed, the exhaust side exhaust valve 17 is opened, and the exhaust means 18 (vacuum pump or the like).
To activate the exhaust connector 1 inside the liquid crystal panel 13.
4. Exhaust through the exhaust pipe 15. This state is continued for a while, and the inside of the liquid crystal panel, including the piping from the injection valve 9 to the injection connector, is brought to a substantially vacuum state.

When the exhaust valve 5 of the outer frame of the liquid crystal container is closed, the injection side atmospheric valve 7 is opened, and the injection valve 9 is opened, the outside pressure of the liquid crystal container 2 is 1 atm and the inside pressure is almost 0 atm. Is sent to the liquid crystal panel due to the pressure difference. The liquid crystal liquid is injected while maintaining this state. In this way, since the liquid crystal liquid once defoamed does not come into contact with the outside air, high quality injection can be realized.

The detailed operation of the liquid crystal liquid supply section is as follows. The bellows-shaped liquid crystal container 2 has a force to restore the original shape. For example, assume that the liquid crystal container 2 in FIG. 6A has an original shape. In this state, the injection valve 9 and the injection side atmospheric valve 7 are closed, the liquid crystal container exhaust valve 19 and the liquid crystal container outer frame exhaust valve 5 are opened, and the exhaust means 6 is operated. The gas dissolved in the liquid crystal liquid is exhausted. At this time,
Since the liquid crystal container exhaust valve 19 is connected to the exhaust means 6,
There is no pressure difference between the inside and outside of the liquid crystal container 2, and the liquid crystal container 2 is not deformed.

When the liquid crystal container exhaust valve 19 and the liquid crystal container outer frame exhaust valve 5 are closed, the liquid crystal liquid does not come into contact with a gas such as the outside air, so that a high-purity liquid crystal liquid can be retained. When the injection valve 9 and the injection side atmospheric valve 7 are opened from this state as described above, the liquid crystal liquid is injected.

In pressure injection, when injecting the liquid crystal liquid, the exhaust side is kept at about 0 atm and the injection side is kept at 1 atm or more. For example, when the atmosphere connected to the injection side atmospheric valve 7 is the atmosphere, the injection part of the liquid crystal liquid becomes about 1 atm, and if the injection side atmospheric valve 7 is supplied with a gas having a pressure of 1 atm or more,
The liquid injection portion has a value of 1 atm or more.

When the liquid crystal liquid fills the space inside the liquid crystal panel, the exhaust side exhaust valve 17 is closed, the exhaust side atmospheric valve 16 is opened, and the exhaust system is opened to the atmosphere. At this time, the pressure on the exhaust side is controlled so as to gradually return to 1 atm, not at once.

When the pressure in the exhaust portion is 0 atm after the injection is completed, the inside of the liquid crystal panel becomes smaller than 1 atm,
On the other hand, since the pressure outside the liquid crystal panel is 1 atm, the liquid crystal panel is slightly recessed, and the liquid crystal liquid is not sufficiently filled. When the filling operation is completed in this state, the liquid crystal panel tries to return to the original flat state due to its own elasticity, so that air flows in from the filling port and the exhaust port of the liquid crystal panel and becomes a defective product. This phenomenon tends to occur as the size of the liquid crystal panel increases, and has become more remarkable as the size of the liquid crystal panel increases.

Therefore, immediately before the injection is completed, or
Immediately before removing the exhaust connector and the injection connector from the liquid crystal panel, the pressure inside and outside the liquid crystal panel must be equal. In reality, the liquid crystal liquid is slowly injected, so by keeping the inlet and exhaust ports of the panel at about 1 atm for a while, the liquid crystal panel changes from a recessed state to a parallel state, and the pressure difference between the inside and the outside is reduced. After fully removing, complete the injection and remove the exhaust connector and injection connector from the LCD panel.

[0014]

However, the above-mentioned conventional method has the following problems. (A) Due to the resilience of the bellows-shaped liquid crystal container itself, even if the container is pressed and deformed with the same pressure, different resilience acts depending on the degree of deformation of the liquid crystal container. Fluid pressure is not kept constant. That is,
As the injection of the liquid crystal liquid progresses, the liquid crystal container 2 gradually contracts as shown in B, C, and D of FIG. 6, but the restoring force of A becomes larger as the contraction progresses.

(B) The self-weight of the liquid crystal liquid remaining in the container is applied, and the injection pressure varies depending on the injection amount.
The liquid crystal liquid 1 therein is in a state of 1 atm or less. (C) When the injection is completed in a completely crushed state as shown in (D), the exhaust connector and the injection connector are removed from the liquid crystal panel, and at the same time, air flows in through the injection port and the exhaust port.
The LCD panel becomes defective.

(D) Due to the position of the liquid crystal container, the valves, the piping, etc., the liquid crystal supply pressure and the pressure of the liquid crystal liquid near the inlet are not always the same. (E) When the injection pressure of the liquid crystal liquid is not accurate, in order to ensure the injection, the liquid crystal arrival sensor that schedules the injection time according to the latest time or determines whether the liquid crystal liquid has been injected This was dealt with by, for example, providing aging until the liquid crystal liquid became stable.

[0017]

The present invention has been made for the purpose of solving the above-mentioned problems, and the invention according to claim 1 provides a liquid crystal pressure vessel and a pressure applying means for applying pressure to the pressure vessel. A pressure device, a control device for controlling the pressurizing device, a valve mechanism for controlling the flow of liquid crystal liquid and air, a supply system for supplying the pressurized liquid crystal liquid, and an exhaust system for exhausting the inside of the liquid crystal panel. The liquid crystal pressurizing and supplying device is characterized in that the pressurizing amount is controlled so that the pressure of the liquid crystal near the liquid crystal liquid inlet of the liquid crystal panel matches the atmospheric pressure outside the liquid crystal panel.

According to a second aspect of the present invention, in the liquid crystal pressure supply device according to the first aspect, a liquid pressure detecting means for detecting the pressure of the liquid crystal liquid injected into the liquid crystal panel is provided, and the detecting means is provided. Control the amount of pressurization based on the detected hydraulic pressure,
It is a liquid crystal pressurizing and supplying device characterized in that the pressure of the liquid crystal near the liquid crystal liquid inlet of the liquid crystal panel is made to match the atmospheric pressure outside the liquid crystal panel.

According to a third aspect of the present invention, in the liquid crystal pressurizing and supplying device according to the first aspect, there is provided a measuring means for measuring the operation amount of the pressurizing device, and the measuring means is added according to the operation amount of the pressurizing means. A liquid crystal pressure supply device characterized by measuring the amount of liquid crystal liquid in a pressure container.

According to a fourth aspect of the present invention, in the liquid crystal pressure supply device according to the third aspect, the control section is provided with a conversion relationship between the expansion / contraction amount of the pressure vessel and the control amount. The liquid crystal pressurizing and supplying device is characterized in that the pressurizing means is controlled based on the expansion / contraction amount of the pressurizing container measured by the operation amount.

The invention according to claim 5 is the same as that of claim 1,
The liquid crystal pressurizing and supplying device described in 2, 3, or 4 has means for judging whether or not the operation amount of the pressurizing device falls within a predetermined range, and the pressure applied to the pressurizing container based on the judgment result. It is a liquid crystal pressure supply device characterized by controlling

According to a sixth aspect of the present invention, in the liquid crystal pressure supply device according to the first aspect, the liquid crystal pressure container has a protrusion on the pressure member, and the liquid crystal liquid container is most compressed. The liquid crystal pressurizing and feeding device is characterized in that the remaining amount becomes very small in the operated state.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <First Embodiment> FIG. 1 shows an embodiment of the present invention. It is a part of a pressure injection device that measures the injection pressure of the liquid crystal liquid near the injection port of the liquid crystal panel and controls the applied pressure to inject the liquid crystal liquid.

The defoamed liquid crystal liquid 1 is a liquid crystal pressure container 102.
The liquid crystal delivery member 103 blocks the external gas. The pressure device 104 is an effector for moving the liquid crystal delivery member 103 up and down, and in the present embodiment, it is composed of a backward movement type cylinder. In this embodiment, compressed air is supplied as the power source 109, and as an example, 5 atm (about 0.5 MPa).
Was supplied. The compressed air delivered from the power source 109 is
It is supplied to the pressurizing device 104 via the pressure adjusting means 105 and 106.

Since the pressure adjusting means 105 operates so as to pull the liquid crystal delivery member 103 into the cylinder in the pressurizing device 104, the pressure adjusting means 105 acts to depressurize the liquid crystal pressurizing container 102. On the contrary, the pressure adjusting means 106 controls the liquid crystal delivery member 10
3 is a pressure adjusting means that operates to send 3 from the pressurizing device 104 and acts in the direction of pressurizing the liquid crystal pressurizing container 102. When the liquid crystal liquid is sent to the panel, the pressure adjusting means 1
Reference numeral 05 is open to the atmosphere, and compressed air is supplied to the pressurizing device 104 using the pressure adjusting means 106.

The liquid pressure measuring means 101 measures the pressure of the liquid crystal liquid 10 near the injection port. This value is input to the control device 108. The control device 108 controls the pressure adjusting means 105, 106 based on the pressure value, and adjusts the pressure of the liquid crystal liquid near the injection port to a target pressure.

FIG. 2 is a flow chart showing an example of this processing procedure. First, the hydraulic pressure is measured 201. If this value is above the target value or exceeds the allowable range, the pressure adjusting means 105 and 106 are controlled so as to reduce the pressure, and this value is below the target value or the target value. Below the range,
The pressure adjusting means 105 and 106 are controlled so as to increase the pressure. Through this work, the pressure at the inlet is always maintained at the target value regardless of the state of the inlet container.

The profile of the pressurizing force may be 1 atm as the target value of the liquid pressure at all times, but in order to shorten the injection time, the value is set to 1.5 atm at the beginning of the injection, and just at the time of completion of the injection. After performing pressure control such as setting the pressure to 1.0 atmosphere and holding it for a while, the exhaust and injection connectors are removed from the liquid crystal panel. At this time, since the liquid crystal panel has returned to its original parallel state, air does not flow from the inlet and the outlet of the liquid crystal panel, and the liquid crystal panel does not become a defective product.

Even if the liquid crystal container is the same as the liquid crystal container 2 of the conventional embodiment and the liquid crystal delivery member 103 is attached to the liquid crystal container 2 to expand and contract the liquid crystal container 2 up and down, the injection side of the conventional embodiment The same control can be performed by adjusting the pressure of the external space 4 of the liquid crystal container through the atmosphere valve 7 to deform the liquid crystal container 2 and controlling the pressure of the liquid crystal liquid.
Further, although compressed air is used as the means for applying pressure in this embodiment, pressurized fluid may be used.

<Second Embodiment> FIG. 3 shows another embodiment of the present invention. This is a part of a liquid crystal injecting device of a system in which when the pressure of the liquid crystal liquid is measured, the moving amount of the uniaxial moving means 124 is measured to indirectly obtain the pressing force and the injection pressure is controlled.

The defoamed liquid crystal liquid 1 is contained in a liquid crystal container 122 capable of expanding and contracting and is shielded from external gas. The protrusion 123 has a shape that minimizes the liquid crystal liquid remaining inside the liquid crystal container in the most compressed state (see FIG. 9F). Liquid crystal liquid is very expensive, but Fig. 6
When the liquid crystal container is in the most contracted state like D, the remaining amount in the container is almost exhausted, the liquid crystal liquid charged in the liquid crystal container is used without waste, and it is effective in cost reduction.

The uniaxial moving means 124 compresses or expands the liquid crystal container 122 up and down to pressurize and supply the liquid crystal liquid.
The uniaxial moving means 124 is driven by a motor which is a uniaxial moving means driving unit 126. In the present embodiment, as an example, DC
Using a motor, the drive unit controller 125 controls the rotation direction and torque, and the uniaxial moving means 124 causes the liquid crystal container 1 to move.
Control the force applied to 22.

The uniaxial moving means driving section 126 is provided with a driving amount detecting means 127 (or a driving section position detecting means). As the drive amount detecting means, for example,
A rotary encoder or a potentiometer is used to detect the operation amount of the uniaxial moving means drive unit 126 from the rotation amount of the motor. That is, the state of the liquid crystal container 122, that is, the height 1 of the liquid crystal container is determined by the information from the drive unit position detection means 127.
29 is measured indirectly.

FIG. 4 shows the relationship between the height 129 of the liquid crystal container and the force applied to the liquid crystal container (in this case, the control amount 130 given to the drive control unit 125). FIG. 4 shows the relationship between the height of the container and the control amount when the liquid pressure near the inlet is 1 atm.
Since the liquid crystal container 122 has a restoring force, in order to make the liquid pressure near the inlet 1 atm, the liquid crystal container is pushed with a greater force as the height 129 of the liquid crystal container is smaller. The control unit 128 in the present embodiment stores a data table of the controlled variable for each liquid pressure near the injection port, which corresponds to FIG. 4, and performs control based on this data table to control the liquid near the injection port. Control the pressure to any required value. It should be noted that such a data table may be created by any method such as one obtained by experiments.

In this embodiment, since the hydraulic pressure is indirectly obtained,
It is not necessary to directly detect the hydraulic pressure as shown in the first embodiment. Further, since the state of the liquid crystal container 122 is monitored, the amount of the remaining liquid crystal liquid and the like can be clearly understood, and the necessity of adding the liquid crystal liquid can be easily determined.

Further, in the present embodiment, when the liquid crystal liquid is leaking, the amount of change per unit time of the detecting portion becomes different from the predetermined value. Therefore, the occurrence of liquid crystal liquid leakage can be detected. When the leak of the liquid crystal is detected, the driving of the motor is stopped immediately. At this time, since the liquid crystal container keeps its shape as it is, the liquid crystal liquid does not spout. Further, in this embodiment, the speed of the motor is limited to avoid the trouble that the liquid crystal liquid blows out all at once.

[0037]

According to the present invention, the following remarkable effects can be obtained by accurately controlling the liquid crystal liquid injection pressure.

The pressure near the liquid crystal inlet of the liquid crystal panel is
It is possible to accurately match the atmospheric pressure outside the liquid crystal panel and make the amount of liquid crystal liquid injected constant. Therefore, the variation in the thickness of the liquid crystal panel is reduced. In addition, since air does not enter the liquid crystal panel, a high quality liquid crystal panel can be produced.

Since the pressure is accurately controlled, the variation of the injection time becomes small, the estimated arrival time of the liquid crystal liquid and the aging time after the arrival are unnecessary, and the injection can be completed in the minimum necessary time. Cost reduction and tact time reduction can be realized.

Since there is a member that directly presses the liquid crystal container, the state of the liquid crystal container can be accurately known from the position and control amount of the member. Therefore, it is possible to know the remaining amount of the liquid crystal liquid and the amount of the liquid crystal liquid injected, and it is possible to easily determine an abnormality such as when the liquid crystal liquid leaks in the pipe or the connector.

The state of the container can be maintained or the deformation speed of the liquid crystal container can be slowed down to minimize the amount of liquid crystal liquid jetted in the case of a trouble such as the panel coming off.

Since the projection is provided in the tank and almost all the liquid crystal liquid in the liquid crystal container can be discharged, it is possible to reduce the waste of the liquid crystal liquid.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment.

FIG. 2 is a diagram showing a flowchart for controlling an injection pressure in the first embodiment.

FIG. 3 is a diagram showing a second embodiment.

FIG. 4 is a diagram showing a relationship between a container height and a control amount in the second embodiment.

FIG. 5 is a diagram showing a conventional example.

FIG. 6 is a diagram showing an operation mode of a liquid crystal container used in a liquid crystal injection device of a conventional example.

FIG. 7 is a diagram showing an injection port and an exhaust port provided in a liquid crystal panel.

FIG. 8 is an enlarged cross-sectional view of a seal portion of a liquid crystal panel.

FIG. 9 is a view showing a protrusion provided inside the tank.

[Explanation of symbols]

1 liquid crystal 2 Liquid crystal container 3 Container outer frame for liquid crystal container 4 External space of liquid crystal container 5 Exhaust valve on the outer frame of liquid crystal container 6 exhaust means 7 Air valve on injection side 8 LCD outlet 9 injection valve 10 Liquid crystal near the inlet 11 Injection connector 12 Injected liquid crystal liquid 13 LCD panel 14 Exhaust connector 15 Exhaust pipe 16 Exhaust side atmospheric pressure valve 17 Exhaust side exhaust valve 18 Exhaust means 19 Liquid crystal container exhaust valve 50 glass panels 51 sealing material 52 Micro beads 53 gap 54 inlet 55 Exhaust port 101 Liquid pressure measuring means 102 Liquid crystal pressure container 103 Liquid crystal delivery member 104 Pressurizing device 105 Pressure adjusting means 106 Pressure adjusting means 108 Control device 109 power source 122 Liquid crystal container 123 protrusion 124 1-axis moving means 125 drive controller 126 1-axis moving means drive unit 128 control unit 129 Height of liquid crystal container 130 controlled variable

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-9-274193 (JP, A) JP-A-8-262461 (JP, A) JP-A-6-43414 (JP, A) JP-A-50- 14362 (JP, A) JP 8-160441 (JP, A) JP 10-48647 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G02F 1/1341 G02F 1 /13

Claims (6)

(57) [Claims] 1. A liquid crystal pressure container, a pressure device for applying pressure to the pressure container, and a control device for controlling the pressure device.
It consists of a valve mechanism that controls the flow of liquid crystal liquid and air, a supply system that supplies pressurized liquid crystal liquid, and an exhaust system that exhausts the inside of the liquid crystal panel.The pressure of the liquid crystal near the liquid crystal liquid inlet of the liquid crystal panel A liquid crystal pressurizing and supplying device characterized in that the amount of pressurization is controlled so that the pressure becomes equal to the atmospheric pressure outside the liquid crystal panel. 2. The liquid crystal pressurizing and supplying device according to claim 1, further comprising a liquid pressure detecting means for detecting the pressure of the liquid crystal liquid injected into the liquid crystal panel, and applying the liquid pressure based on the liquid pressure detected by the detecting means. A liquid crystal pressurizing and supplying device characterized by controlling the amount of pressure so that the pressure of the liquid crystal near the liquid crystal inlet of the liquid crystal panel matches the atmospheric pressure outside the liquid crystal panel. 3. The liquid crystal pressurizing and supplying device according to claim 1, further comprising a measuring means for measuring an operation amount of the pressurizing device,
A liquid crystal pressurizing and supplying device characterized in that the liquid crystal liquid amount in the pressurizing container is measured by the operation amount of the pressurizing means. 4. The liquid crystal pressurizing and supplying device according to claim 3, wherein the control section is provided with a conversion relationship between the expansion / contraction amount of the pressurizing container and the control amount, and the pressurizing container is measured by the operating amount of the pressurizing device. A liquid crystal pressurizing and supplying device characterized in that the pressurizing means is controlled based on the amount of expansion and contraction of the liquid crystal. 5. The liquid crystal pressure supply device according to claim 1, 2, 3 or 4, further comprising means for determining whether or not the operation amount of the pressure device falls within a predetermined range, and the determination result A liquid crystal pressurizing and supplying device characterized in that the pressure applied to the pressurizing container is controlled based on the above. 6. The liquid crystal pressurizing and supplying device according to claim 1, wherein the liquid crystal pressurizing container is provided with a protrusion on the pressing member, and the remaining amount of the liquid crystal liquid container is very small when the liquid crystal liquid container is most compressed. A liquid crystal pressure supply device characterized by the following.