JP2019211081A5 - - Google Patents

Description

FIG. 8 is a diagram showing the relationship between the curvature R and the fully closed pressing pressure F, and FIG. 9 is a diagram showing the relationship between the curvature R and the strain E. The "fully closed pressing pressure" means the pressing force required to deform the tubular body 3 by the pressing portion 4 driven by the driving unit 5 to bring the pinch valve 1 into the fully closed state, and "strain" is In the fully closed state, it refers to the strain in the most deformed portion of the tubular body 3, for example, the portion of the tubular body 3 with which the tip end portion of the pressing portion 4 abuts. The strain E is a value obtained by dividing the change in length before and after deformation by the length before deformation.

The pinch valve 100 according to the second embodiment has, in addition to a primary seal for ensuring airtightness during normal use, a seal portion which is a secondary seal in case the tubular body 3 ruptures. As a result, even if the pipe body 3 bursts, the fluid inside the pipe body 3 does not flow out to the outside of the pinch valve 100. Specifically, the pinch valve 100 has an annular protrusion 133 as a first seal member, an O-ring 25 as a second seal member, and an O-ring 17 as a fourth seal member as a seal portion. , These seal the fluid communication between the space near the outer surface of the tubular body 3 and the outside of the pinch valve 100. As described above, the pinch valve 100 according to the second embodiment does not have a configuration corresponding to the O-ring 29 which is the third seal member of the first embodiment. The annular projection 133 may be replaced with an O-ring.

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