US 12,467,458 B2
Variable capacity bypass valve for screw compressor
Jonathan D. Batdorff, Fort Wayne, IN (US); Hideki Fujimoto, Shizuoka (JP); and Edward Noble, Chesterton, IN (US)
Assigned to HITACHI GLOBAL AIR POWER US, LLC, Michigan City, IN (US)
Appl. No. 18/727,307
Filed by HITACHI GLOBAL AIR POWER US, LLC, Michigan City, IN (US)
PCT Filed Jan. 20, 2022, PCT No. PCT/US2022/013169
§ 371(c)(1), (2) Date Jul. 8, 2024,
PCT Pub. No. WO2023/140851, PCT Pub. Date Jul. 27, 2023.
Prior Publication US 2025/0084845 A1, Mar. 13, 2025
Int. Cl. F04C 28/26 (2006.01); F04C 18/16 (2006.01)
CPC F04C 28/265 (2013.01) [F04C 18/16 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A variable capacity bypass valve for a screw compressor having a compressor housing defining a compression chamber, the variable capacity bypass valve comprising:
a bore formed in a rotor bore discharge face of the compressor housing upstream of a compression chamber outlet end of the compression chamber;
a slide valve member inserted into the bore to fill a cavity formed in the rotor bore discharge face of the compressor housing, the valve member having a sealing surface configured to interact with a thread of a compressor screw during operation of the screw compressor; and
an actuator structure coupled to the valve member and oriented to move the valve member radially along the bore to open a fluid pathway communicatively coupling the compression chamber to a bypass chamber configured to return compressed fluid to a fluid inlet of the compression chamber,
wherein the valve member has a partial cylindrical shape with an opened region on a side opposite the sealing surface in an axial direction of the screw compressor.