Abstract: A hollow board cutting apparatus includes a machine bed unit, a driving unit, and a cutting unit. The driving unit includes a pair of upper sprockets rotatably disposed on the machine bed unit, a pair of lower sprockets rotatably disposed on the machine bed unit, a motor coupled to one of the lower sprockets for directly driving rotation of the one of the lower sprockets, a first drive chain trained on the upper and lower sprockets, and a second drive chain trained on the lower sprockets. The cutting unit includes an upper positioning seat coupled co-movably to the first drive chain, a lower positioning seat coupled co-movably to the second drive chain, and at least one cutting blade secured between the upper and lower positioning seats.

Abstract: A hand-free handset and neckband arrangement includes a neckband for hanging on the user's neck, a slide coupled to the neckband and moved to adjust the diameter of the neckband, a swivel hook fastened to the slide, a quick-release plug coupled to the swivel hook, a quick-release socket detachably fastened to the quick-release plug, the quick-release plug being provided with a loop for holding a cellular telephone, and a hand-free handset installed in the neckband for enabling the user to use the cellular telephone with the hands free for doing things.

Abstract: A fan blade sign display device includes a rotary device, an actuator adapted to rotate the rotary device, a display unit installed in the rotary device, and a control device adapted to turn on/off the display unit. A sign is appeared in the movement path of the LED array upon rotation of the LED array with the rotary device at the speed in which the motion cycle of the LED array is smaller than the transient retention time of visual sensation when controlling the control device to turn on/off the display unit.

Abstract: A hand-free handset and neckband arrangement includes a neckband for hanging on the user's neck, a slide coupled to the neckband and moved to adjust the diameter of the neckband, a swivel hook fastened to the slide, a quick-release plug coupled to the swivel hook, a quick-release socket detachably fastened to the quick-release plug, the quick-release plug being provided with a loop for holding a cellular telephone, and a hand-free handset installed in the neckband for enabling the user to use the cellular telephone with the hands free for doing things.