# US 5,701,741 A · Turbochargers for internal combustion engines > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,701,741 A - Document ID: US5701741A - Status: Granted - Kind: A - Application number: 08/481,406 - Filed: 1995-09-08 - Granted: 1997-12-30 - Earliest claimed: 1993-11-11 - Assignees: AlliedSignal Inc. - Inventors: Philip S. Halsall - Web page: https://patentgrep.com/patent/US5701741A ## CPC - F02B 37/183: {Arrangements of bypass valves or actuators therefor} - F02B 37/18: by bypassing exhaust {from the inlet to the outlet of turbine or to the atmosphere} - F02B 37/186: {Arrangements of actuators or linkage for bypass valves} - Y02T 10/12: Improving ICE efficiencies - F02B: INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL (gas-turbine plants F02C; hot-gas or combustion-product positive-displacement engine plants F02G) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A turbocharger has a drive-shaft mounted in bearing means in a housing. The drive shaft drivably connects an exhaust gas driven turbine wheel to the impeller of an air compressor 22. A gas flow control device, such as a wastegate 10, 39 and/or a variable geometry turbine inlet nozzle, positioned upstream of the turbine wheel is operable to adjust the operating performance of the turbocharger. An electrically drivable actuator motor 17, 45, such as a D.C. motor or a stepper motor, is provided for regulating the operation of the gas flow control device via a linkage means 14, 15, 405, 407, 406, 825, 830, 835 in response to an electrical signal dependent at least upon the delivery pressure of the compressor. In a preferred arrangement the linkage means includes a relatively rotatable threaded lead screw 15 and a correspondingly threaded female screw member 14 threadably engaged therewith. ## Claims ### Claim 1 Turbocharger comprising a drive-shaft mounted in bearing means in a housing, the drive-shaft drivably connecting an exhaust gas driven turbine wheel to the impeller of a compressor, a gas flow control device positioned upstream of the turbine wheel and operable to adjust the operating performance of the turbocharger, and an electrically drivable actuator motor for regulating the operation of the gas flow control device via linkage means in response to an electrical signal dependent at least upon delivery pressure of the compressor, the linkage means comprising a male threaded lead screw having a multistart thread and a correspondingly female threaded screw member threadedly engaged therewith and one of said screw member and lead screw being arranged to move generally linearly, substantially parallel to an axis of the drive-shaft, on rotation of the other of said screw member and lead screw by the actuator motor, thereby converting said rotation into movement of the gas flow control device. ### Claim 2 (depends on 1) A turbocharger as claimed in claim 1, wherein the female screw member is rotated by driving of the actuator motor. ### Claim 3 (depends on 1) A turbocharger as claimed in claim 1, wherein the generally linearly movable one of said threaded lead screw and said screw member is provided with means for adjusting the longitudinal extent of the linkage means. ### Claim 4 (depends on 1) A turbocharger as claimed in claim 1, wherein the gas flow control device comprises means for varying the geometry of a nozzle at an exhaust gas input to the turbine wheel. ### Claim 5 (depends on 4) A turbocharger as defined in claim 4 wherein the linkage means further includes a yoke having an attachment operably interconnected to the lead screw for linear translation in response to linear translation of the lead screw and the means for varying the geometry comprises a cylindrical sleeve and means for connecting the sleeve to the yoke. ### Claim 6 (depends on 5) A turbocharger as defined in claim 5 wherein the yoke includes a pivot distal from the attachment for rotation of the yoke in response to the linear translation of the lead screw and the means for connecting the sleeve to the yoke comprises two pins extending radially inward with respect to an axis of translation of the sleeve and engaging the sleeve. ### Claim 7 (depends on 1) A turbocharger as claimed in claim 1, wherein the actuator motor comprises a DC motor. ### Claim 8 (depends on 1) A turbocharger as claimed in claim 1, wherein output of the actuator motor passes to the linkage means through a reducing gearbox. ### Claim 9 (depends on 1) A turbocharger as claimed in claim 1, wherein the linkage means is arranged to translate rotary motion of an output shaft of the actuator into generally linear movement of the gas flow control device. ### Claim 10 (depends on 1) A turbocharger as claimed in claim 1, wherein an axis of rotation of the actuator motor is positioned generally parallel to, and offset from, an axis of the turbocharger drive-shaft.