초록 ▼

A compressor wheel is re-designed to permit die inserts (20), which occupy the air passage and define the blades (4, 5) during a process of forming a wax pattern (21) of a compressor wheel, to be pulled without being impeded by the blades. This modified blade design enables the automated production

A compressor wheel is re-designed to permit die inserts (20), which occupy the air passage and define the blades (4, 5) during a process of forming a wax pattern (21) of a compressor wheel, to be pulled without being impeded by the blades. This modified blade design enables the automated production of wax patterns (21) using simplified tooling. These wax patterns (21) can be used in a large-scale investment casting process, and produce an economical cast titanium compressor wheel which performs aerodynamically at high boost pressure/RPM. The compressor wheel improves low cycle fatigue, withstands high temperatures and temperature changes, and permits operation at high boost pressure ratio while, on the other hand, having low weight, low inertial drag, and high responsiveness. An economical method for operating an internal combustion engine, comprising providing the engine with an easily manufactured, long-life titanium compressor wheel and driving the titanium compressor wheel at high RPM for increasing combustion air throughput and density.

대표청구항 ▼

1. A titanium centrifugal compressor wheel formed by an investment casting process, and including: a hub defining an axis of rotation, and a plurality of backswept aerodynamic blades carried on the surface of said hub and defining air passages between adjacent blades, wherein each of said air p

1. A titanium centrifugal compressor wheel formed by an investment casting process, and including: a hub defining an axis of rotation, and a plurality of backswept aerodynamic blades carried on the surface of said hub and defining air passages between adjacent blades, wherein each of said air passages is defined by from one to three solid die inserts which can be inserted between and pulled from between said blades without deformation of said dies or blades. 2. A titanium compressor wheel as in claim 1, wherein the number of die inserts necessary to define the air passage between said blades is three . 3. A titanium compressor wheel as in claim 1, wherein the number of die inserts necessary to define the air passage between said blades is two. 4. A titanium compressor wheel as in claim 1, wherein the number of die inserts necessary to define the air passage between said blades is one. 5. A cast titanium centrifugal compressor wheel comprising: an annular hub defining an axis of rotation, and a plurality of backswept aerodynamic blades, each of said blades including a leading edge, an outer edge adapted for close passage to a compressor housing, and a trailing edge, wherein said leading edge is substantially a straight edge, wherein said blades are designed such that a single solid die insert defining the space between adjacent blades can be inserted between adjacent blades and retracted along a radial or curved path. 6. A cast titanium compressor wheel as in claim 5, wherein said compressor wheel is comprised of a titanium-aluminum alloy. 7. A cast titanium centrifugal compressor wheel comprising: an annular hub defining an axis of rotation, and a plurality of backswept aerodynamic blades, each of said blades including a leading edge, an outer edge adapted for close passage to a compressor housing, and a trailing edge, wherein said leading edge is substantially a straight edge, wherein said blades are designed such that a compound die insert comprising first and second solid die inserts defining one air passage between adjacent blades can be inserted between said adjacent blades, and wherein said first and second die inserts can be retracted along a radial or curved path without deformation of said blades or dies.