Abstract: A device for detecting a missing element on a circuit board comprising a positioning tray, a data processing assembly, a lifting control assembly, and a detecting assembly. The positioning tray supports and positions a circuit board to be tested. The data processing assembly is connected with the lifting control assembly and the detecting assembly, and sends a control signal to the lifting control assembly, receives detection data sent by the detecting assembly, and compares the detection data with preset reference data to obtain a detection result of a missing element. The detecting assembly moves up and down between an initial position and a preset position under the control of the lifting control assembly, and sends the detection data to the data processing assembly according to a contact state with elements on the circuit board to be tested at the preset position.

Abstract: A rotary shock-testing machine including: a base; a first shaft rotatable relative to the base, the first shaft being driven to rotate; a first wheel rotatable with the first shaft; a second shaft rotatable relative to the base; a second wheel rotatable with a first portion of the second shaft; and a test disc for holding one or more specimens to be tested, the test disc being rotatable with a second portion of the second shaft; wherein the first and second wheels are aligned with each other such that the second wheel is driven by the first wheel when a material is introduced into a gap between a surface of the first wheel and a corresponding surface of the second wheel.

Abstract: A relay driving apparatus to be automatically restores a relay driving state if the relay is inadvertently turned off. The relay driving apparatus supplies a predetermined rated voltage to the relay RL1 to shift the relay RL1 to a driving state and then reduces the voltage to maintain the driving state of the relay RL1. The driving state of the relay RL1 is monitored, and on the basis of the monitoring result the relay RL1 is again provided with the rated driving voltage. Alternatively, the rated voltage is periodically supplied to the relay RL1 during the driving state, or after a predetermined rated voltage is supplied to the relay RL2 to set the relay RL2 to a driving state or non-driving state, the state is monitored and the relay RL2 is periodically subjected to the rated driving operation on the basis of the monitoring result, thereby enhancing the operation reliability and promoting energy savings.

Abstract: A novel test lead can be used to connect an aging line with a voltage or multi-meter in order to monitor the voltage output by the aging line. The aging line is used to age electronic devices and components, particularly cathode ray tubes, during the manufacturing process. The test lead includes a plug adapted for ready connection to an output socket of the aging line without requiring any disassembly of the socket. The other end of the test lead preferably includes a number of clips, banana or alligator, for connecting the lead to the voltage or multi-meter. In this way, the output voltage of the aging line can be easily and rapidly tested for conformance with predetermined specifications.

Abstract: The present invention provides an aqueous gel comprising a polymer of (meth)acrylamide or particular (meth)acrylamide derivative(s), particulate metal oxide(s) and an aqueous medium, a process for producing said gel, and products utilizing said gel.This aqueous gel can be produced so as to have transparency, has fire resistance and can prevent the spreading of flames, and is highly elastic. The aqueous gel, when produced as a transparent gel, becomes cloudy when heated or cooled and is useful for the shielding of heat rays or cold radiation.