TWI386254B - Spray apparatus and liquid crystal dispenser with the spray apparatus - Google Patents

Description

Spraying device and liquid crystal coating machine having the same

The present invention relates to a coater for discharging liquid crystals to a panel region defined on a mother substrate.

Liquid crystals are intermediate phases between crystalline solids and isotropic liquids and combine certain properties of crystal structures and deformed fluids. Liquid crystal displays (LCDs) utilize the anisotropy associated with the fluidity of liquid crystals and the crystallization characteristics. Liquid crystal displays are used in mobile phones, portable computers, desktop monitors, and LCD TVs.

The liquid crystal display is composed of a TFT array substrate, a color filter array substrate, and a liquid crystal layer interposed therebetween.

By controlling the voltage applied to the liquid crystal layer of each pixel, different amounts of light can be allowed to pass, and different degrees of gray scale are formed.

The liquid crystal coater is used to apply liquid crystal on either of the TFT array substrate and the color filter array substrate, and is hereinafter referred to as "mother substrate (M)".

A panel area is defined on the mother substrate. The liquid crystal coater applies a reference liquid crystal amount to each panel region.

1A, 1B, and 1C are schematic views showing a panel region U defined by a conventional liquid crystal coater dropping liquid crystal droplets from a nozzle on a mother substrate.

As shown in FIG. 1A, the liquid crystal coater drops the liquid crystal droplet D from the nozzle N positioned above the predetermined panel area U.

As shown in FIG. 1B, the liquid crystal droplets collide with the panel region, causing its shape to change rapidly. As a result, portions of the liquid crystal droplets are forced to break into pieces P. At the same time, air replaces portions of the liquid crystal droplets, thereby trapping inside the remaining liquid crystal droplets.

As shown in Figure 1C, the debris P bounces off the panel area and falls elsewhere.

The debris P may fall on a rectangular sealant pattern formed around the panel area. In the subsequent attachment procedure, the two mother substrates are not attached to each other well. The debris P may fall outside the rectangular sealant pattern. This makes the reference liquid crystal amount of the panel area U short.

Then, the air A trapped inside the liquid crystal droplets causes the liquid crystal layer interposed between the two mother substrates to generate air bubbles.

Since the liquid crystal droplets fall in the panel region with a considerable impact, after the two mother substrates M are attached, the liquid droplet marks S are presented on the LCD panel.

Accordingly, it is an object of the present invention to coat the respective panel regions defined on the mother substrate with the same amount of liquid crystal as the reference liquid crystal.

It is an object of the present invention to drop a plurality of liquid crystals equal to the reference liquid crystal amount on each of the panel regions defined on the mother substrate.

Another object of the invention is to avoid trapping air within the liquid crystal droplets.

Another object of the present invention is to prevent the droplet marks from being present on the LCD panel after the two mother substrates are attached to each other.

According to an aspect of the invention, there is provided a liquid crystal coater comprising: a main frame; a platform provided on the main frame; a coating head unit support frame movably connected to the main frame; a first driving unit, a moving coating head unit a support frame; a second driving unit provided on the coating head unit support frame; and a spraying device connected to the coating head unit support frame, which is movable by the second driving unit.

The spraying device comprises: a supporting assembly movably connecting the coating head unit supporting frame; a cylinder assembly having an inflow port and an outflow port on the outer surface thereof, detachably connecting the supporting assembly; and a spraying unit spraying the liquid crystal discharged from the outflow outlet On the mother substrate.

The foregoing and other objects, features, aspects and advantages of the present invention will become apparent from

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the preferred embodiment of the invention, and the accompanying drawings,

2 is a perspective view of a coater for coating a liquid crystal according to an embodiment of the present invention. 3 is a schematic view of the spraying device 190 shown in FIG. 2.

As shown in FIGS. 2 and 3, the liquid crystal coating machine includes a main frame 100, a stage 110, a coating head unit support frame 130, a first driving unit 140, a second driving unit 150, and a spraying device 190.

The platform 110 is movably provided on the upper side of the main frame 100. The platform 110 may be fixedly provided on the upper side of the main frame 100.

Platform 110 is in the form of a hexahedron.

The first guiding unit 160 is provided on the main frame 100. The first guiding unit 160 includes two first guiding members 161 and two first sliders 162, and slidably connects the two first guiding members 161, respectively. The two first guiding members 161 are connected to the main frame 100 at intervals in parallel with each other.

The cross section of the first guiding member 161 is a quadrangle.

The first slider 162 is coupled to the bottom side of the platform 110.

A motor (not shown) that drives the platform 110 is provided to the main frame 100. The motor contains a linear motor.

The coating head unit support frame 130 is movably provided on the upper side of the main frame 100 in such a manner as to straddle the platform 110. A spray device 190 is provided to the coating head unit support frame 130.

The second guiding unit 170 is provided on the main frame 100 to guide the movement of the coating head unit support frame 130. The coating device 190 is coupled to the coating head unit support frame 130.

The second guiding unit 170 includes two second guiding members 171 and two second sliders 172 respectively slidably connecting the two second guiding members 171. The two second guiding members 171 are connected to the main frame 100 at intervals in parallel with each other.

The second guiding member 171 has a quadrangular cross section. The second guiding members are configured to be parallel to each other. The longitudinal direction of the second guiding member 171 is the Y-axis direction.

The first guiding member 161 is positioned between the second guiding members 171.

The coating head unit support frame 130 includes a horizontal body 131 and two vertical bodies 132 that are respectively connected to both sides of the horizontal body.

The horizontal body 131 is perpendicular to the vertical body 132. One end of the vertical body 132 is connected to a second slider 172 that is coupled to a second guiding member 171. One end of the other vertical body 132 is connected to another second slider 172 that is coupled to the other second guiding member 171.

The first driving unit 140 that moves the coating head unit support frame 130 is provided to the main frame 100. The first drive unit 140 includes a linear motor, and a rotary motor and a ball screw that connects the rotary motor.

Two coating head unit support frames 130 are movably provided to the main frame 100.

One or more spray devices 190 are provided to the coating head unit support frame 130. The spraying device 190 connects the coating head unit support frame 130 with the third guiding unit 180. The spraying device 190 can be moved by the third guiding unit 180.

The third guiding unit 180 includes a third guiding member 181 and a third slider 182. The third guiding member 181 is coupled to one side of the horizontal body 131. The third slider 182 is connected to the third guiding member 181, respectively. The third guiding member 181 has a rectangular cross section. The third guiding members 181 are parallel to each other. The third guiding member 181 is provided on the horizontal body 131 and is the same as the longitudinal direction of the horizontal body 131.

The second driving unit 150 is provided to the coating head unit support frame 130. The second drive unit 150 moves the spray device 190.

A support assembly 200 constituting the spraying device 190 is provided to the third slider 182.

Figure 4 is a schematic vertical cross-sectional view of the cylinder assembly shown in Figure 3.

As shown in FIGS. 3 and 4, the spraying device 190 includes a support assembly 200, a cylinder assembly 300, a piston 400, a liquid crystal supply unit 500, a rotary drive unit 700, a linear drive unit 800, and a spray unit 900.

The support assembly 200 includes a first support member 210 that connects the third slider 182, a second support member 220 that connects the bottom side of the first support member 210, and a support shell 230 that connects the second support member 220.

The second support member 220 separates the support case 230 from the first support member 210 from each other.

The support shell 230 includes a side plate 233 having a hole 231 on the side, a side plate 233 connecting the two sides of the rear plate 232, and a bottom member 234 connecting the bottom side of the rear plate 232.

The connecting unit 240 includes a bolt 241 and a nut 242 that is respectively locked to the bolt 241. Bolts 241 are provided at a distance from each other at the bottom of the bottom member 234. Preferably, two pairs of bolts 241 and nuts 242 are provided.

The second drive unit 150 can include a linear motor.

The cylinder assembly 300 is detachably attached to the connection unit 240.

The cylinder assembly 300 includes a cylindrical block 310 having a groove 311, a piston bore 321, and a cylinder 320. The connecting unit 240 may be attached to the groove 311 and detachable from the groove 311. The piston 400 is inserted into the piston bore 321 . The cylinder 320 has an inflow port 322 and an outflow port 323, both of which are connected to the piston hole 321. The cylinder 320 is inserted into the cylindrical block 310.

A cover member 340 covering the piston hole 321 is provided on the bottom side of the cylinder 320.

The cover member 340 can be transparent while allowing the piston hole 321 to be seen.

The cylinder block 310 is attached to the bottom member 234 by inserting the bolt 241 into the groove 311 and locking the nut 242 to the bolt 241, respectively. Therefore, the cylindrical block 310 is fixed to the connecting unit 240.

The cylinder block 310 can be removed from the bottom member 234 by removing the nut 242 from the bolt 241 and separating it from the groove 311, respectively. Therefore, the cylindrical block 310 can be detached from the connecting unit 240.

The piston 400 is inserted into the piston bore 321 of the cylinder 320.

The piston 400 includes a rod member 410 and a connecting portion 420 extending from one end of the rod member 410.

The rod 410 has a groove 430 formed in the longitudinal direction of the circumferential surface of the rod.

When the groove 430 faces the inflow port 322, the inflow port 322 is opened, and at this time, the outflow port 323 is closed. When the groove 430 faces the outflow port 323, the outflow port 323 is opened, and at this time, the inflow port 322 is closed.

The liquid crystal supply unit 500 is connected to the inflow port 322 of the cylinder 320.

The liquid crystal supply unit 500 includes a bottom plate 510, a bottle 520, and a first tube 530. The bottom plate 510 is provided on the support case 230. A bottle 520 containing liquid crystal is placed on the bottom plate 510. The first tube 530 is connected between the bottle 520 and the inflow port 322 of the cylinder 320 to carry the liquid crystal from the bottle 520 to the inflow port 322.

The connecting portion 420 of the piston 400 is detachably attached to the shaft 705 of the rotary drive unit 700. When the connecting portion 420 attaches the shaft 705, the rotary driving unit 700 rotates the piston 400.

The linear drive unit 800 is provided to the support case 230. The linear drive unit 800 moves the rotary drive unit 700 up and down.

The linear drive unit 800 includes a moving member 810, a first fixing member 820, a second fixing member 830, a third rotation motor 840, and a ball screw 850. The moving member 810 is fixedly coupled to the rear side of the base member 710 constituting the rotary driving unit 700, and protrudes from the surface of the rear plate 232 through the hole 231 of the rear plate 232. The first fixing member 820 is provided on the upper side of the rear plate 232. The second fixing member 830 is provided on the lower side of the rear plate 232. The third rotation motor 840 is provided to the first fixing member 820. The ball screw 850 is coupled between the moving member 810 and the second fixing member 830. The ball screw 850 is rotatable by the third rotary motor 840 to move the moving member 810 up and down.

The liquid crystal discharged through the outflow port 323 is sprayed on the mother substrate M as shown in FIG. 7 through the spraying unit 900.

Figure 5 is a schematic view showing a pipe connected between the spray unit and the outlet of the cylinder assembly.

As shown in FIG. 5, the pipe member 990 is connected between the spray unit 900 and the outflow port 323, and the spray unit 900 is provided on the support plate 980. The support plate 980 is connected to the support assembly 200 as shown in FIG.

Figure 6 is a front elevational view of the spray unit of Figure 5. Figure 7 is a schematic view showing the spray unit spraying liquid crystal on the panel area.

As shown in FIGS. 6 and 7, the spray unit 900 includes a housing 910, a connecting tube 920, a piezoelectric device 930, a cable 940, a first shock absorber 951, and a second shock absorber 952. The housing 910 includes an inlet 911 and an outlet 912 through which liquid crystal flows into the housing 910 and through which the liquid crystal is sprayed. The connecting pipe 920 is connected between the inlet 911 and the outlet 912. Piezoelectric device 930 vibrates connection tube 920. Cable 940 carries current to piezoelectric device 930. The first shock absorber 951 is located between the connecting pipe 920 and the inlet 911. The second shock absorber 952 is located between the connecting tube 920 and the outlet 912.

The inlet 911 is connected to the outflow port 323 by a pipe 990. The liquid crystal discharged through the outflow port 323 passes through the tube 990 and the inlet 911 and flows into the connection pipe 920.

A piezoelectric device 930 in the form of a donut is inserted into the housing 910 and surrounds the connecting tube 920. Piezoelectric device 930 can be in the form of any vibrating connection tube 920. When an electric field is applied, the piezoelectric device 930 generates mechanical stress, thereby vibrating the connection tube 920.

The higher the frequency of the current supplied to the piezoelectric device 930 through the cable 940, the more the connection tube 920 vibrates. The connection tube 920 can vibrate at a frequency greater than 20 KHz.

The vibration of the connecting tube 920 causes the liquid crystal flowing into the connecting tube 920 to vibrate. This causes the liquid crystal L to break into very small particles C.

As a result, liquid crystal L is sprayed through the outlet 912.

The first shock absorber 951 and the second shock absorber 952 prevent the housing 910 from vibrating when the connecting tube 920 vibrates. The first shock absorber 951 and the second shock absorber 952 may not be provided. In this case, the housing 910 also vibrates. The first shock absorber 951 and the second shock absorber 952 may be made of rubber capable of absorbing vibration.

The operation of spraying the liquid crystal on the panel area defined on the mother substrate will now be described.

As shown in FIGS. 3 and 4, the rotary drive unit 700 rotates the piston 400 such that the groove 430 of the piston 400 faces the inlet 322 of the cylinder. Once the groove 430 faces the inflow port 322, the rotary drive unit 700 stops rotating the piston 400.

The linear drive unit 800 moves the rotary drive unit 700 upward by a predetermined distance. This also moves the piston 400 up.

The suction space is formed on the bottom side of the piston and the upper side of the cover member 340 in the piston hole 321 . The higher the piston 400 moves upward, the larger the suction space, and the lower the pressure in the piston bore 321 becomes. The pressure difference between the inside and the outside of the cylinder causes the liquid crystal in the bottle 520 to flow into the suction space through the first tube 530 and the inflow port 322.

Once the piston 400 is moved upward by a predetermined distance, the linear drive unit 800 stops moving the piston 400 upward. Then, the rotary drive unit 700 rotates the piston 400 such that the groove 430 of the piston 400 faces the outflow port 323 of the cylinder 320.

Once the groove 430 faces the outflow port 323, the rotary drive unit 700 stops rotating the piston 400.

The linear drive unit 800 moves the rotary drive unit 700 downward by a predetermined distance. This will also move the piston 400 down.

The lower the piston 400 moves downward, the smaller the suction space. The downward movement of the piston 400 forces the liquid crystal in the suction space to be discharged to the outside through the outflow opening 323.

As shown in FIG. 7, the liquid crystal discharged through the outflow port 323 flows into the connecting pipe 920 through the pipe 990 and the inlet 911 of the spraying unit 900.

When an electric field is applied, the piezoelectric device 930 generates mechanical stress, thereby vibrating the connecting tube 920 at a frequency greater than 20 KHz.

The vibration of the connecting tube 920 causes the liquid crystal L flowing into the connecting tube 920 to vibrate. This causes the liquid crystal L to break into very small particles C.

As shown in FIG. 7, these very small liquid crystal particles fall through the outlet 912 in the panel region U.

FIG. 8 is a schematic view showing four regions in which the liquid crystal sprayed by the spray unit falls on each of the four panel regions defined on the mother substrate.

As shown in FIG. 8, very small liquid crystal particles C are placed in four regions of the respective panel regions of the four panel regions U.

Since the weight of very small liquid crystal particles is much smaller than the weight of liquid crystal droplets, very small liquid crystal particles do not bounce off from the panel region than liquid crystal droplets. This ensures that very small liquid crystal particles do not fall elsewhere, such as on a sealant (glue) pattern. Therefore, the need to compensate for the shortage of liquid crystals is eliminated. Furthermore, since the impact of very small liquid crystal particles falling on the panel region is much smaller, the droplets are not marked on the LCD panel after the two mother substrates are attached to each other.

While the present invention may be embodied in many forms without departing from the spirit and scope of the invention, it is to be understood that the invention is not limited to the details of the foregoing description. The following broad description is intended to cover all such changes and modifications as may fall within the spirit and scope of the invention as defined by the scope of the invention. range.

100. . . Main frame

110. . . platform

130. . . Coating head unit support frame

131. . . Horizontal subject

132. . . Vertical body

140. . . First drive unit

150. . . Second drive unit

160. . . First guiding unit

161. . . First guiding member

162. . . First slider

170. . . Second guiding unit

171. . . Second guiding member

172. . . Second slider

180. . . Third guiding unit

181. . . Third guiding member

182. . . Third slider 182

190. . . Spraying device

200. . . Support assembly

210. . . First support member

220. . . Second support member

230. . . Support shell

231. . . Hole

232. . . Back plate

233. . . Side panel

234. . . Bottom member

240. . . Connection unit

241. . . bolt

242. . . Nut

300. . . Cylinder assembly

310. . . Cylinder block

311. . . Groove

320. . . Cylinder

321. . . Piston hole

322. . . Inflow

323. . . Outflow

340. . . Cover

400. . . piston

410. . . Lever

420. . . Connection

430. . . Trench

500. . . Liquid crystal supply unit

510. . . Bottom plate

520. . . Bottle

530. . . First tube

700. . . Rotary drive unit

705. . . Shaft

710. . . Base piece

800. . . Linear drive unit

810. . . Moving member

820. . . First fixing member

830. . . Second fixing member

840. . . Third rotary motor

850. . . Ball screw

900. . . Spray unit

910. . . case

911. . . Entrance

912. . . Export

920. . . Connecting pipe

930. . . Piezoelectric device

940. . . Cable

951. . . First shock absorber

952. . . Second shock absorber

980. . . Support plate

990. . . Pipe fittings

A. . . air

C. . . Liquid crystal particle

D. . . Liquid crystal drop

L. . . liquid crystal

M. . . Mother substrate

N. . . nozzle

P. . . Fragmentation

S. . . Droplet

U. . . Panel area

The accompanying drawings are included to provide a further understanding of the embodiments of the invention

1A, FIG. 1B, and FIG. 1C are schematic diagrams showing a panel region U defined by a conventional liquid crystal coating machine from a nozzle drop liquid crystal on a mother substrate;

2 is a perspective view of a coater for coating a liquid crystal according to an embodiment of the present invention;

Figure 3 is a schematic view of the spraying device shown in Figure 2;

Figure 4 is a vertical sectional view of the cylinder assembly shown in Figure 3;

Figure 5 is a schematic view showing a pipe connected between the spray unit and the outlet of the cylinder assembly;

Figure 6 is a front view of the spray unit shown in Figure 5;

Figure 7 is a schematic view showing the spray unit spraying liquid crystal on the panel area;

FIG. 8 is a schematic view showing four regions in which the liquid crystal sprayed by the spray unit falls on each of the four panel regions defined on the mother substrate.

900‧‧‧Spray unit

910‧‧‧Shell

911‧‧‧ entrance

912‧‧ Export

920‧‧‧Connecting tube

930‧‧‧ Piezoelectric device

940‧‧‧ cable

951‧‧‧First shock absorber

952‧‧‧Second shock absorber

990‧‧‧ pipe fittings

C‧‧‧ liquid crystal particles

L‧‧‧LCD

M‧‧‧ mother substrate

U‧‧‧ panel area

Claims (7)

A spraying device comprising: a cylinder assembly having a first-class inlet and a first-class outlet; and a spraying unit spraying the liquid crystal discharged from the outlet port on a mother substrate, wherein the spraying unit comprises: a connecting tube, wherein the liquid crystal flows through the connection a piezoelectric device that vibrates the connecting tube; and a cable that carries current to the piezoelectric device. The spraying device of claim 1, wherein the spraying unit further comprises: a casing having an inlet and an outlet through which the liquid crystal flows into the casing, and the liquid crystal is sprayed through the outlet, wherein the spraying A tube is disposed within the housing and coupled between the inlet and the outlet. The spraying device of claim 2, wherein the vibration of the connecting tube causes the liquid crystal flowing into the connecting tube to vibrate, thereby causing the liquid crystal to break into very small particles and escaping through the outlet to the outside. The spraying device of claim 2, wherein the higher the frequency of the current supplied to the piezoelectric device through the cable, the more the connecting tube vibrates. The spraying device of claim 4, wherein the connecting tube vibrates at a frequency greater than 20 KHz. The spraying device of claim 2, further comprising: a first shock absorber located between the connecting pipe and the inlet; and a second shock absorber between the connecting pipe and the outlet. A liquid crystal coating machine comprising: a main frame; a platform provided on the main frame; a coating head unit support frame movably connecting the main frame; a first driving unit, moving the coating head unit a support frame; a second driving unit is provided on the coating head unit support frame; and a spraying device connected to the coating head unit support frame, the second driving unit is movable, the spraying device comprises: a supporting component, Removably connecting the coating head unit support frame; a cylinder assembly having a first-class inlet and a first-class outlet on the outer surface thereof, detachably connecting the support assembly; and a spray unit spraying the liquid crystal discharged from the outlet port a mother substrate, wherein the spray unit comprises: a connecting tube, wherein the liquid crystal flows through the connecting tube; a piezoelectric device vibrates the connecting tube; and a cable that carries current to the piezoelectric device.