Abstract: The present disclosure relates to the technical field of fiber-optic gas sensing and laser photoacoustic spectroscopy, and reliability of a gas detection system is improved by actively selecting a working frequency of low noise interference combined with an optical fiber photoacoustic sensing probe capable of isolating high-frequency noise. A gas enters a photoacoustic microcavity through gaps on a sound-sensitive diaphragm after diffusing into a miniature air chamber through a plurality of micropores. Photoacoustic excitation light is incident into the photoacoustic microcavity through a fiber-optic collimator and then excited to generate a photoacoustic pressure wave to cause the sound-sensitive diaphragm to vibrate periodically. An end face of a single-mode optical fiber and the sound-sensitive diaphragm constitutes a fiber-optic Fabry-Perot interferometer. The interferometer measures a deflection of the diaphragm and inverts a concentration of the to-be-measured gas.

Abstract: A battery protection board includes a first circuit board, a second circuit board, and a tab connecting portion. The first circuit board includes a first substrate, electronic components and an insulation layer. The first substrate includes a first surface and a second surface opposite to each other. The electronic components are disposed on the first surface and the insulation layer covers the electronic components on the first surface. The second circuit board includes a second substrate. The second substrate includes a third surface and a fourth surface opposite to each other. The third surface is connected with the second surface. The tab connecting portion is disposed on the fourth surface. The first substrate has sufficient space reserved for welding the second substrate improving reliability of connection between the first and the second circuit boards, optimizing spatial layout of the battery protection board and ensuring versatility of first circuit board.

Abstract: An enclosure can include a top enclosure portion having a top flange and a first top engagement feature. The enclosure can also include a bottom enclosure portion mechanically coupled to the top enclosure portion, where the bottom enclosure portion has a bottom flange that mechanically couples to the top flange and a first bottom engagement feature that mechanically couples to the first top engagement feature. The enclosure can further include a first fastening device mechanically and movably coupled to the first top engagement feature and the first bottom engagement feature. The first fastening device, in an engaged position, can maintain a flame path between the top flange and the bottom flange. The first fastening device, in a disengaged position, can fail to maintain a flame path between the top flange and the bottom flange.

Abstract: The current invention discloses a thrust lever ball head assembly comprising a thrust lever ball hinge and a thrust lever ball head. The thrust lever ball head comprises a main body of the thrust lever ball head and flange structures on both sides of the main body of the thrust lever ball head, wherein the flange structures and the main body of the thrust lever ball head are an integral part, and the flange structures on both sides of the main body of the thrust lever ball head work together with the thrust lever ball hinge to limit the thrust lever ball hinge inside the thrust lever ball head. The thrust lever ball head assembly of the present invention has a simple structure, high assembling efficiency, low manufacture costs, light weight, free of maintenance and completely fulfills the requirements of light weight.

Abstract: The current invention discloses a thrust lever ball head assembly comprising a thrust lever ball hinge and a thrust lever ball head. The thrust lever ball head comprises a main body of the thrust lever ball head and flange structures on both sides of the main body of the thrust lever ball head, wherein the flange structures and the main body of the thrust lever ball head are an integral part, and the flange structures on both sides of the main body of the thrust lever ball head work together with the thrust lever ball hinge to limit the thrust lever ball hinge inside the thrust lever ball head. The thrust lever ball head assembly of the present invention has a simple structure, high assembling efficiency, low manufacture costs, light weight, free of maintenance and completely fulfills the requirements of light weight.

Abstract: An enclosure can include a top enclosure portion having a top flange and a first top engagement feature. The enclosure can also include a bottom enclosure portion mechanically coupled to the top enclosure portion, where the bottom enclosure portion has a bottom flange that mechanically couples to the top flange and a first bottom engagement feature that mechanically couples to the first top engagement feature. The enclosure can further include a first fastening device mechanically and movably coupled to the first top engagement feature and the first bottom engagement feature. The first fastening device, in an engaged position, can maintain a flame path between the top flange and the bottom flange. The first fastening device, in a disengaged position, can fail to maintain a flame path between the top flange and the bottom flange.

Abstract: An enclosure can include a top enclosure portion having a top flange and a first top engagement feature. The enclosure can also include a bottom enclosure portion mechanically coupled to the top enclosure portion, where the bottom enclosure portion has a bottom flange that mechanically couples to the top flange and a first bottom engagement feature that mechanically couples to the first top engagement feature. The enclosure can further include a first fastening device mechanically and movably coupled to the first top engagement feature and the first bottom engagement feature. The first fastening device, in an engaged position, can maintain a flame path between the top flange and the bottom flange. The first fastening device, in a disengaged position, can fail to maintain a flame path between the top flange and the bottom flange.

Abstract: An enclosure can include a first enclosure portion having a first flange, at least one first engagement feature disposed on a first inner surface of the first enclosure portion, and at least one mounting support. The enclosure can also include a second enclosure portion mechanically coupled to the first enclosure portion and having a second flange and at least one second engagement feature disposed on a second inner surface of the second enclosure portion. The enclosure can further include at least one fastening device mechanically and movably coupled to the at least one mounting support, where the at least one fastening device engages the first flange and the second flange when the one fastening device is in a closed position, and where the at least one fastening device is disengaged from the first flange and the second flange when the one fastening device is in an open position.

Abstract: An enclosure can include a top enclosure portion having a top flange and a first top engagement feature. The enclosure can also include a bottom enclosure portion mechanically coupled to the top enclosure portion, where the bottom enclosure portion has a bottom flange that mechanically couples to the top flange and a first bottom engagement feature that mechanically couples to the first top engagement feature. The enclosure can further include a first fastening device mechanically and movably coupled to the first top engagement feature and the first bottom engagement feature. The first fastening device, in an engaged position, can maintain a flame path between the top flange and the bottom flange. The first fastening device, in a disengaged position, can fail to maintain a flame path between the top flange and the bottom flange.

Abstract: An enclosure can include a first enclosure portion having a first flange, at least one first engagement feature disposed on a first inner surface of the first enclosure portion, and at least one mounting support. The enclosure can also include a second enclosure portion mechanically coupled to the first enclosure portion and having a second flange and at least one second engagement feature disposed on a second inner surface of the second enclosure portion. The enclosure can further include at least one fastening device mechanically and movably coupled to the at least one mounting support, where the at least one fastening device engages the first flange and the second flange when the one fastening device is in a closed position, and where the at least one fastening device is disengaged from the first flange and the second flange when the one fastening device is in an open position.

Abstract: A fastening device for fastening a cover to a body of an explosion-proof enclosure can include a bracket having a back side mechanically coupled to a bottom side at a first angle and to a top side at a second angle, where the top side includes an engagement portion, where the first angle is substantially parallel to an under side of the body flange, and where the second angle is substantially parallel to a top side of the cover flange. The fastening device can also include a cam fixedly coupled to an outer surface of the cover flange and hingedly coupled to the engagement portion. The fastening device can further include a lever fixedly coupled to the cam and having a closed position and an open position.

Abstract: An enclosure system that can include an enclosure cover comprising a receiving feature. The enclosure system can also include an enclosure body mechanically coupled to the enclosure cover. The enclosure system can further include a cover release mechanism mechanically coupled to the enclosure body and disposed at least in part, within the receiving feature, where the cover release mechanism is movable between a first position and a second position. The enclosure cover and the enclosure body can be mechanically coupled to each other when the cover released mechanism is in the first position. The enclosure cover and the enclosure body can be, at least in part, separated from each other when the cover release mechanism moves to the second position from the first position.

Abstract: A fastening device for fastening a cover to a body of an explosion-proof enclosure can include a bracket having a back side mechanically coupled to a bottom side at a first angle and to a top side at a second angle, where the top side includes an engagement portion, where the first angle is substantially parallel to an under side of the body flange, and where the second angle is substantially parallel to a top side of the cover flange. The fastening device can also include a cam fixedly coupled to an outer surface of the cover flange and hingedly coupled to the engagement portion. The fastening device can further include a lever fixedly coupled to the cam and having a closed position and an open position.