Patent Publication Number: US-10758945-B2

Title: Liquid knife, liquid knife cleaning apparatus and liquid knife assembly apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to Chinese application No. 201610161409.0, filed Mar. 21, 2016, which is hereby incorporated by reference in its entirety. 
     TECHNICAL FIELD 
     The disclosure relates to the field of displays, and in particular, to a liquid knife, a liquid knife cleaning apparatus and a liquid knife assembly apparatus. 
     BACKGROUND 
     The primary purpose of a color film factory in the tin film transistor-liquid crystal display (TFT-LCD) is to coat photoresist of different colors on a glass substrate and prepare patterns of different colors through exposure, development, post-baking and other processes. The purpose of the developing process of the color film factory is to remove unexposed photoresist on the substrate, retain the exposed photoresist pattern, rinse the glass substrate after exposure with a solution of diluted potassium hydroxide (KO) and then rinse the glass substrate with pure water to remove KO residual liquid. A liquid knife apparatus is added in a connection region between a developing section and a cleaning section of a developing device to rapidly clear the KO residual liquid and development residue on a surface of the substrate, thereby reducing the blocking of a filter in the cleaning section. However, water curtain bifurcation may occur in the uninterrupted production of the liquid knife for a long period of time, and the main reason is because the development residue or other foreign matter falls into a knife edge of the liquid knife and blocks a flow direction. The bifurcated liquid curtain generated due to the residual foreign matter in the liquid knife causes poor development, generating the poor development (Mura) and other undesirable qualities. 
     To solve the above-mentioned problem, an approach in the related art includes manually cleaning liquid curtain after the equipment is shut down. Specifically, the primarily actions include stuffing a sheet inside a knife edge of a liquid knife in a developing machine, cleaning the interior of the knife edge of the liquid knife automatically back and forth several times in a certain speed, regularly cleaning the residual foreign matter inside the liquid knife in a certain frequency, and the production line is resumed after the cleaning is confirmed to be OK. However, the utilization of the equipment is affected and there is a risk of poor products. 
     SUMMARY 
     An object of the disclosure is to provide a liquid knife cleaning apparatus, a liquid knife and a liquid knife assembly apparatus. The liquid knife cleaning apparatus can replace the conventional manual cleaning way to clean a knife edge of a liquid knife, and can reduce the probability of the liquid curtain bifurcation occurring, thereby reducing the probability of a development MURA occurring and improving utilization of the apparatus. 
     Technical solutions according to the disclosure are provided as follows. 
     A liquid knife cleaning apparatus is adapted to clean a liquid knife with a knife edge. The liquid knife cleaning apparatus includes: a frame configured to be arranged on the liquid knife and be capable of reciprocating in an extending direction of the knife edge; a cleaning blade configured to extend into the knife edge of the liquid knife and be capable of reciprocating inside the knife edge under driving of the frame to clean the knife edge, the cleaning blade being arranged on the frame; and a movable mechanism configured to control the frame to reciprocate on the liquid knife in the extending direction of the knife edge, the frame being connected to the movable mechanism. 
     Further, the frame includes: a first side frame and a second side frame arranged on two opposite sides of the liquid knife; and a bottom frame arranged below the knife edge of the liquid knife, the bottom frame being connected to the first side frame and the second side frame. The cleaning blade is arranged on the bottom frame. 
     Further, the frame is V-shaped. 
     Further, the liquid knife cleaning apparatus includes an adjustment scroll configured to adjust a first height of the cleaning blade extending into the knife edge. 
     Further, the adjustment scroll includes a scroll arranged on the frame; the cleaning blade is a soft blade, one end of the cleaning blade extends toward the knife edge of the liquid knife, the other end of the cleaning blade is wound on the scroll, and the rotation of the scroll can control the soft blade to be stretched out and drawn back to adjust the first height of the cleaning blade extending into the knife edge. 
     Further, the adjustment scroll further includes a restriction component arranged on the scroll. 
     Further, a guide rail is arranged in the extending direction of the knife edge on the liquid knife; the movable mechanism includes: a movable component configured to be cooperated with the guide rail on the liquid knife and reciprocate on the guide rail, the movable component being arranged on the frame; and a driving structure configured to drive the movable component to move on the guide rail. 
     Further, the guide rail includes: protruding portions protruded on two sides of the liquid knife and extending in the extending direction of the knife edge; the movable component includes: hook portions capable of being cooperated with the protruding portions. 
     Further, the guide rail includes: groove structures arranged in two sides of the liquid knife and extending in the extending direction of the knife edge; the movable component includes: hook portions capable of being cooperated with the groove structures. 
     Further, the movable mechanism further includes: a control unit configured to control an operating state of the driving structure to control a moving state of the frame, thereby controlling an operating state of the cleaning blade. 
     A liquid knife includes a cooperating structure cooperated with the movable mechanism of the liquid knife cleaning apparatus as described above. 
     Further, the cooperating structure includes: a guide rail arranged in the extending direction of the knife edge, and the guide rail is arranged on the liquid knife. 
     Further, the guide rail includes: protruding portions protruded on two sides of the liquid knife and extending in the extending direction of the knife edge; or the guide rail includes: groove structures arranged in two sides of the liquid knife and extending in the extending direction of the knife edge. 
     A liquid knife assembly apparatus is provided according to the disclosure, which includes: a liquid knife with a knife edge and a liquid knife cleaning apparatus. The liquid knife cleaning apparatus includes a frame and a cleaning blade arranged on the frame and corresponding to the knife edge. The frame is slidably sleeved on the liquid knife. 
     Further, the frame is V-shaped, and at least part of the knife edge is in the frame. 
     Further, the cleaning blade is inside the frame. 
     Further, the liquid knife assembly apparatus further includes a guide rail on the liquid knife, and a movable mechanism on the frame. The guide rail and the movable mechanism are cooperated with each other to control the frame to be slidable relative to the liquid knife in an extending direction of the knife edge. 
     Further, the movable mechanism includes a movable component slidably installed on the guide rail and a driving structure connected to the movable component. 
     The disclosure has advantageous effects as follows. 
     The liquid knife cleaning apparatus can replace the conventional manual cleaning way to clean the knife edge of the liquid knife, can reduce the probability of the liquid curtain bifurcation occurring, thereby reducing the probability of a development MURA occurring, improving utilization of the apparatus as well as avoiding other problems caused by discontinuous process. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a liquid knife in the related art; 
         FIG. 2  is a front view of the liquid knife in the related art; 
         FIG. 3  is a front view of a liquid knife according to one embodiment of the disclosure; 
         FIG. 4  is a perspective view of the liquid knife according to one embodiment of the disclosure; 
         FIG. 5  is a schematic diagram of a liquid knife cleaning apparatus according to one embodiment of the disclosure; 
         FIG. 6  is a schematic diagram of the liquid knife cleaning apparatus when cleaning a liquid knife according to one embodiment of the disclosure; 
         FIG. 7  illustrates a schematic front view of normal liquid curtain ejected by a liquid knife; 
         FIG. 8  illustrates a schematic front view of abnormal liquid curtain ejected by a liquid knife; and 
         FIG. 9  is a schematic diagram of a liquid knife cleaning apparatus according to one embodiment of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     As required, detailed embodiments are disclosed herein. However, it is to be understood that the disclosed embodiments are merely exemplary and that various and alternative forms may be employed. The figures are not necessarily to scale. Some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art. 
     To make the object, technical solutions and advantages of the disclosure more clear, in the following, the technical solutions in embodiments of the disclosure are illustrated clearly and completely in conjunction with the accompanying drawings of the embodiments of the disclosure. It is apparent that the described embodiments are only a part of embodiments of the present disclosure, rather than all embodiments. Other embodiments obtained by those skilled in the art on the basis of the described embodiments of the present disclosure without creative work fall into the scope of protection of the present disclosure. 
       FIG. 1  and  FIG. 2  are schematic diagrams of a liquid knife of a cleaning device or a development device in the related art. The liquid knife is mainly made of SUS (stainless steel) material. As shown in  FIG. 1  and  FIG. 2 , the liquid knife  1  has a slit-shaped knife edge  2 , and all slit widths of the knife edge  2  of the liquid knife  1  are substantially identical. The slit widths of the knife edge  2  of the liquid knife  1  generally are of 0.1 mm±0.015 mm. Cleaning agent or developer liquid flows uniformly out of slits of the knife edge  2  of the liquid knife  1  to rinse a surface of the substrate. Liquid curtain bifurcation (as shown in  FIG. 8 ) may occur in the uninterrupted production and usage of the liquid knife for a long period of time, even seriously, developing horizontal line (Mura) may occur. 
     The approach of cleaning the liquid knife in the related art includes: necessarily shutting down the equipment, inserting a thin-long cleaning blade (film) into the knife edge of the liquid knife to scrape inner walls of the knife edge of the liquid knife from left to right and back to left, finishing the cleaning operation when it is visually observed that the fluid flow is not bifurcated, and then restarting the equipment subsequently, which causes the utilization of the equipment to be decreased and tends to improve a risk in quality. 
     As shown in  FIGS. 3-6 , a liquid knife cleaning apparatus according to embodiments of the disclosure includes a frame  200 , a cleaning blade  300  and a movable mechanism. 
     The frame  200  is to be arranged on a liquid knife  100  and is capable of reciprocating in an extending direction of a knife edge  101  of the liquid knife  100 . 
     The cleaning blade  300  is to extend into the knife edge  101  of the liquid knife  100  and is capable of reciprocating inside the knife edge  101  under the driving of the frame  200  to clean the knife edge  101 . The cleaning blade  300  is arranged on the frame  200 . 
     The movable mechanism is to control the frame  200  to reciprocate on the liquid knife  100  in the extending direction of the knife edge  101 . The frame  200  is connected to the movable mechanism. 
     The liquid knife cleaning apparatus according to the disclosure can replace the conventional manual cleaning way to clean the knife edge  101  of the liquid knife  100 , and can reduce the probability of the liquid curtain bifurcation occurring, thereby reducing the probability of a development MURA occurring, improving the utilization of the apparatus as well as avoiding other problems caused by discontinuous process. 
     An optional example of the liquid knife cleaning apparatus according to one embodiment of the disclosure is illustrated below. 
     In one embodiment, optionally, as shown in  FIGS. 5-6 , the frame  200  includes: a first side frame  201 , a second side frame  202  and a bottom frame  203 . The first side frame  201  and the second side frame  202  are arranged on two opposite sides of the liquid knife  100 . The bottom frame  203  is arranged below the knife edge  101  of the liquid knife  100 . The bottom frame  203  is connected to the first side frame  201  and the second side frame  202 . The cleaning blade  300  is arranged on the bottom frame  203 . 
     As shown in  FIG. 5 , in the above-described technical solution, a V-shaped structure is defined by the first side frame  201 , the second side frame  202  and the bottom frame  203  of the frame  200 , which is matched with the liquid knife  100 . It should be understood that the structure of the frame  200  may be in various forms in actual applications, which is not limited herein. 
     In addition, in one embodiment, optionally, the liquid knife cleaning apparatus further includes an adjustment scroll configured to adjust a first height of the cleaning blade  300  extending into the knife edge  101 . 
     In the above-described technical solution, the first height of the cleaning blade  300  which extends into the knife edge  101  of the liquid knife  100  may be adjusted by the adjustment scroll. Therefore, the liquid knife cleaning apparatus is adapted to clean knife edges  101  of different depths. 
     In one embodiment, optionally, as shown in  FIG. 9 , the adjustment scroll includes a scroll  600  arranged on the frame  200 . The cleaning blade  300  is a soft blade. One end of the cleaning blade  300  extends toward the knife edge  101  of the liquid knife  100 , and the other end of the cleaning blade  300  is wound on the scroll  600 . The rotation of the scroll  600  can control the soft blade to be stretched out and drawn back to adjust the first height of the cleaning blade  300  extending into the knife edge  101 . 
     In the above-described technical solution, the first height of the soft blade extending into the knife edge  101  can be adjusted by rotating the scroll to stretch out and draw back the soft blade. The scroll and the soft blade are cooperated in the adjustment scroll, with a simple structure and easy operation. It can be understood that, the adjustment scroll may be configured to be other structures, which are not listed one by one herein. 
     In addition, it should be noted that, the adjustment scroll further includes a restriction component  602  arranged on the scroll for restricting the cleaning blade  300 , in a case that the first height of the cleaning blade  300  extending into the knife edge  101  is a specified height, as shown in  FIG. 9 . 
     Moreover, in the embodiment, the structure of the liquid knife  100  is modified to be matched with the liquid knife cleaning apparatus according to the embodiment of the disclosure. As shown in  FIG. 3 ,  FIG. 4  and  FIG. 6 , a guide rail  102  is arranged in the extending direction of the knife edge  101  on the liquid knife  100  according to the embodiment of the disclosure. 
     In the embodiment, the movable mechanism includes a movable component and a driving structure  605 . The movable component is cooperated with the guide rail  102  on the liquid knife  100  and reciprocates on the guide rail  102 . The movable component is arranged on the frame  200 . The driving structure  605  is to drive the movable component to move on the guide rail  102 , as shown in  FIG. 9 . 
     In the above-described technical solution, the guide rail  102  is added on an outer wall of the liquid knife  100  according to the disclosure, and is used to hold the liquid knife cleaning apparatus according to the embodiment of the disclosure. The liquid knife cleaning apparatus is fixed on the liquid knife  100  through engagement between the movable component on two sides of the frame  200  and the guide rail  102  on two sides of the liquid knife  100 . When a cleaning operation is not performed, the frame  200  stays at a location closest to the right edge of the liquid knife  100 , which may not cause liquid curtain bifurcation. The guide rail  102  is cooperated with the movable component on the frame  200  to control a movement direction of the frame  200 . A driving force for the movement of the frame  200  is supplied by the driving structure. The liquid knife cleaning apparatus is fixed on the liquid knife  100  via a guiding mechanism such as the guide rail  102  on two sides of the liquid knife  100 . The driving structure may specifically be in various forms, for example, a form of cooperating a screw rod with a servo motor, or a form of cooperating a spiral rod with a driving motor. The specific driving structure is not limited herein. 
     In this embodiment, optionally, as shown in  FIG. 3 ,  FIG. 4  and  FIG. 6 , the guide rail  102  includes: protruding portions protruded on two sides of the liquid knife  100  and extending in the extending direction of the knife edge  101 . The movable component includes: hook portions  204  cooperated with the protruding portions. The hook portions  204  may hook on the protruding portions. 
     In the above-described technical solution, the frame  200  is fixed on the liquid knife  100  by cooperating the protruding portions with the hook portions  204 , with a simple cooperating structure of the protruding portions and the hook portions  204 , which prevents abnormal fall risk. 
     In other embodiments of the disclosure, there may be several forms of cooperating the guide rail  102  of the liquid knife  100  with the movable component of the liquid knife cleaning apparatus. For example, the guide rail  102  includes: groove structures arranged in two sides of the liquid knife  100  and extending in the extending direction of the knife edge  101 . The movable component includes: hook portions capable of being cooperated with the groove structures. It can be understood that, a specific cooperating structure of the guide rail  102  and the movable component is not limited herein. 
     In addition, in the embodiment of the disclosure, the movable mechanism further includes: a control unit  607  configured to control an operating state of the driving structure to control a moving state of the frame  200  and thus control an operating state of the cleaning blade  300 , as shown in  FIG. 9 . 
     In addition, the control unit is further configured to control an operating state of the scroll to control the first height of the cleaning blade  300  extending into the knife edge  101 . 
     In the above-described technical solution, the control unit may control the frame  200  to clean the inner walls of the liquid knife  100  along the guide rail  102  via wireless signals. A cleaning duration, a cleaning interval and the first height of the cleaning blade  300  of the liquid knife cleaning apparatus may be set and controlled. 
     The liquid knife cleaning apparatus according to the optional embodiment of the disclosure may be automatically clean the liquid knife  100  in a production interval in a case of not being shut down. The cleaning blade  300  of the apparatus is used to scrape the knife edge  101  of the liquid knife  100  back and forth to remove the residues, thereby reducing a risk in quality due to liquid curtain bifurcation. The liquid knife cleaning apparatus may adjust a cleaning frequency and a cleaning duration according to actual situations, for example, which can be set and controlled via a touch screen. 
     With the liquid knife cleaning apparatus according to the optional embodiment of the disclosure, the periodical cleaning may further be realized to prevent a risk of liquid curtain bifurcation abnormality occurring, thereby ensuring that the liquid curtain state is as shown in  FIG. 7  after the cleaning is completed. If liquid curtain bifurcation occurs as shown in  FIG. 8  in the production, the developing process may be paused at once, a setting operation may be performed on the touch screen and a cleaning operation is performed promptly, thereby ensuring the quality to be normal without seriously affecting the utilization of the equipment. 
     Furthermore, a liquid knife is provided according to one embodiment of the disclosure, which includes a cooperating structure cooperated with the movable mechanism of the liquid knife cleaning apparatus as described above. 
     Optionally, as shown in  FIG. 3  and  FIG. 4 , in the liquid knife  100  according to one embodiment of the disclosure, the cooperating structure includes: a guide rail  102  arranged in the extending direction of the knife edge  101 . The guide rail  102  is arranged on the liquid knife  100 . 
     Optionally, as shown in  FIG. 3  and  FIG. 4 , in the liquid knife  100  according to one embodiment of the disclosure, the guide rail  102  includes: protruding portions protruded on two sides of the liquid knife  100  and extending in the extending direction of the knife edge  101 ; or the guide rail  102  includes: groove structures arranged in two sides of the liquid knife  100  and extending in the extending direction of the knife edge  101 . 
     Furthermore, a liquid knife assembly apparatus is further provided according to one embodiment of the disclosure. As shown in  FIG. 6 , the liquid knife assembly apparatus includes: a liquid knife  100  having a knife edge  101  and a liquid knife cleaning apparatus. The liquid knife cleaning apparatus includes a frame and a cleaning blade arranged on the frame and corresponding to the knife edge  101 . The frame is slidably sleeved on the liquid knife  100 . 
     The above-described embodiments are only preferred embodiments of the present disclosure. It should be noted that various modifications and substitutions may be made to the disclosure for those skilled in the art without departing from the technical principle of the disclosure, and these modifications and substitutions are also considered to fall into the protective scope of the disclosure. 
     While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.