US 12,276,200 B2
Variable displacement exhaust turbocharger
Yuya Nakahara, Tokyo (JP); Toyotaka Yoshida, Tokyo (JP); Yosuke Dammoto, Sagamihara (JP); and Yoji Akiyama, Sagamihara (JP)
Assigned to MITSUBISHI HEAVY INDUSTRIES ENGINE & TURBOCHARGER, LTD., Sagamihara (JP)
Appl. No. 17/601,604
Filed by MITSUBISHI HEAVY INDUSTRIES ENGINE & TURBOCHARGER, LTD., Sagamihara (JP)
PCT Filed May 9, 2019, PCT No. PCT/JP2019/018517
§ 371(c)(1), (2) Date Oct. 5, 2021,
PCT Pub. No. WO2020/225898, PCT Pub. Date Nov. 12, 2020.
Prior Publication US 2022/0178271 A1, Jun. 9, 2022
Int. Cl. F01D 17/16 (2006.01); F02B 37/22 (2006.01); F02C 6/12 (2006.01)
CPC F01D 17/165 (2013.01) [F02B 37/22 (2013.01); F02C 6/12 (2013.01); F05D 2200/211 (2013.01); F05D 2200/221 (2013.01); F05D 2200/261 (2013.01); F05D 2200/262 (2013.01); F05D 2200/263 (2013.01); F05D 2220/40 (2013.01); F05D 2240/128 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A variable displacement exhaust turbocharger, comprising:
a plurality of nozzle vanes;
an annular drive ring; and
a lever plate fitted at one end in a groove portion disposed in the drive ring via a connecting pin portion and connected at another end to each nozzle vane,
wherein, for each nozzle vane, a value of dimensionless slippage S between the groove portion and the connecting pin portion is equal to or less than 0.0016 when the dimensionless slippage S is represented by the following equation (A):
S={(L+rp+r)cos(Φmx+Ψ)}−1[r sin θmx−(L+r)sin Φmx×dΦ/dθ+{(L+r)cos Φmx−L−r cos θmx}tan θmx+Ψ)dΦ/dθ]+rp(1−dΦ/dθ)/(L+rp+r)  (A)
where r is a distance between a central position of the connecting pin portion and a rotation center of the nozzle vane,
rp is a radius of the connecting pin portion,
L is a distance between a rotation center of the drive ring and the rotation center of the nozzle vane,
Ψ is an angle of a wall surface of the groove portion formed to be contactable with the connecting pin portion with respect to a radial direction of the drive ring,
θ is an angle between a line segment passing through the rotation center of the drive ring and the rotation center of the nozzle vane and a line segment connecting the central position of the connecting pin portion to the rotation center of the nozzle vane,
θmx is a possible maximum value of the angle θ,
Φ is a rotation angle of the drive ring based on an angular position of the drive ring when the angle θ is 0 degrees,
Φmx is the rotation angle Φ when the angle θ is θmx, and
dΦ/dθ in the equation (A) is represented by the following equation (B):
dΦ/dθ={r cos θmx+r sin θmx tan(Φmx+Ψ)}/[(L+r cos θmx){1+tan2(Φmx+Ψ)}−(L+r)tan(Φmx+Ψ){cos Φmx tan(Φmx+Ψ)−sin Φmx}]  (B).