With reference to
With reference to
The bracket (20) is made of static electrically conductive material such as metal to conduct electricity. The bracket (20) is detachably mounted on the top end of the shaft (10) and comprises a center, a bottom, a central hole (21) and a sleeve (22). The central hole (21) is defined through the center of the bracket (20) and communicates with the vacuum pump through a tube so that the vacuum pump may provide a suction effect in the central hole (21). The sleeve (22) protrudes down from the bottom of the bracket (20), is mounted around the top end of the shaft (10) and comprises a cavity (221), a positioning hole (223) and a bolt (225). The cavity (221) is defined axially in the sleeve and receives the top end of the shaft (10). The positioning hole (223) is defined radially in the sleeve (22), communicates with the cavity (221) and is threaded. The bolt (225) is mounted detachably through the positioning hole (223) and extends into the mounting slot (11) in the shaft (10) so that the shaft (10) and the base (20) can be fastened together.
The disk (30) is mounted on the base (20), may contact and hold a glass substrate, is made of static electrically conductive material such as carbon, graphite, metal and the like to conduct electricity. Preferably, a resistivity of the disk (30) is 103 to 105 ohms/sq. The disk (30) comprises a center, a top, a through hole (31), multiple radial gaps (32) and multiple annular gaps (33). The through hole (31) is defined through the center of the disk (30) and communicates with the central hole (21) in the bracket (20). The radial gaps (32) are defined in the top of the disk (30) and communicate with the through hole (31). The annular gaps (33) are defined in the top of the disk (30), communicate with the radial gaps (32) and are arranged concentrically. When the vacuum pump operates, the suction effect provided by the vacuum pump reaches in the radial and annular gaps (31, 32) to securely hold a glass substrate on the chuck.
With reference to
Therefore, the disk (30), the base (20), the chuck with the disk (30) allows the static electricity to discharge through the static electricity discharging pathway so the glass substrate on the disk is not damaged by the static electricity. Therefore, a production rate of the glass substrate is increased.
Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and features of the invention, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.