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| sherpa [28.06.2023 17:15] – gerdlothar | sherpa [28.06.2023 17:24] (current) – [The compressor technology] gerdlothar |
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| * **Crown seal:**\\ The ingenious idea is to do without the [[screw-down crown]], but to use the rising water pressure for sealing. This technology, called Monoflex, was developed in the 1950s by Ervin Piquerez S.A. ([[EPSA]]) and updated by Sherpa. \\ In this process, higher external pressure leads to pressure on the seal towards the tube, while the pressure decreases or disappears at lower (or no) pressure. The sealing materials used here are not common in the watch industry and are very long lasting and resistant agains wear. | * **Crown seal:**\\ The ingenious idea is to do without the [[screw-down crown]], but to use the rising water pressure for sealing. This technology, called Monoflex, was developed in the 1950s by Ervin Piquerez S.A. ([[EPSA]]) and updated by Sherpa. \\ In this process, higher external pressure leads to pressure on the seal towards the tube, while the pressure decreases or disappears at lower (or no) pressure. The sealing materials used here are not common in the watch industry and are very long lasting and resistant agains wear. |
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| * **Case bottom seal:** \\ {{wst>image_cr|Sherpa|Ultradive back|Case back of the Sherpa Ultradive with the traditional EPSA diving helmet logo|200px}} The caseback design follows the same compression principle: the "compressor" system used to be a snap-on caseback, which could be compressed further into the case/gasket to increase pressure onto the gasket in order to increase waterproofness. The currently used compressor system in Sherpa models is the EPSA STOP, which is an improved bayonet compressor system.\\ In this way, on deeper dives, the rising water pressure automatically pushes a screw-down caseback deeper into the case, resulting in a tighter fit. | * **Case bottom seal:** \\ {{wst>image_cr|Sherpa|Ultradive back|Case back of the Sherpa Ultradive with the traditional EPSA diving helmet logo|200px}} The caseback design follows the same compression principle: the "compressor" system used to be first a caseback with a snap-on latch that could be compressed to increase water tightness. The "EPSA-STOP" or "bayonet compressor" system was a further development of this system, where the case bottom did not snap into place, but was secured by a sophisticated bayonet system that also allowed the case bottom to be compressed under water pressure.\\ In this way, during deeper dives, the rising water pressure automatically pushes a screwed caseback deeper into the case, resulting in firmer pressure on the seal. |
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| * **The Sherpa update:** \\ The "EPSA-STOP" or "Bayonet Compressor" system has been improved through the use of advanced sealing materials and increased manufacturing precision, as well as a new design. This allows the caseback to be inserted in only one orientation and guarantees a perfectly aligned EPSA logo (the iconic diving helmet!) on the caseback. \\ This new design makes the caseback so tight to the gasket that everyday actions can be performed easily and safely, while the gasket becomes even tighter when the watch is subjected to higher external pressure. | * **The Sherpa update:** \\ The "EPSA-STOP" or "Bayonet Compressor" system has been improved through the use of advanced sealing materials and increased manufacturing precision, as well as a new design. This allows the caseback to be inserted in only one orientation and guarantees a perfectly aligned EPSA logo (the iconic diving helmet!) on the caseback. \\ This new design makes the caseback so tight to the gasket that everyday actions can be performed easily and safely, while the gasket becomes even tighter when the watch is subjected to higher external pressure. |
