# US 2014/0194240 A1 · Journal pin oil supply for gear system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0194240 A1 - Document ID: US20140194240A1 - Status: Published application - Kind: A1 - Application number: 14/204,031 - Filed: 2014-03-11 - Published: 2014-07-10 - Earliest claimed: 2011-08-02 - Assignees: United Technologies Corporation - Applicants: United Technologies Corporation - Inventors: Michael E. McCune - Web page: https://patentgrep.com/patent/US20140194240A1 ## CPC - F16H 57/043: {within rotary parts, e.g. axial channels or radial openings in shafts} - F02C 7/32: Arrangement, mounting, or driving, of auxiliaries - F16C 33/02: Parts of sliding-contact bearings - F16H 57/0479: {Gears or bearings on planet carriers} - F05D 2260/40311: of the epicyclical, planetary or differential type - F16C 2360/23: Gas turbine engines - F16C 2361/61: Toothed gear systems, e.g. support of pinion shafts - F16H 2057/085: {Bearings for orbital gears} - Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft - Y10T 29/49464: Assembling of gear into force transmitting device - F16H: GEARING - F02C: GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS (construction of turbines F01D; jet-propulsion plants F02K; construction of compressors or fans F04; generating combustion products of high pressure or high velocity F23R; using gas turbines in compression refrigeration plants F25B11/00) - F16C: SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract An example journal pin includes a generally cylindrical body disposed on an axis having a supply passage. A first chamber and a second chamber are disposed in the generally cylindrical body and are in fluid communication with the supply passage. A recess on an outer diameter of the cylindrical body is in fluid communication with the first chamber and the second chamber. The first chamber and second chamber are each radially outward of the supply passage and including an outlet to the recess. The first chamber and second chamber each have a first section radially inward of a second section. A cross sectional area of the second section is greater than a cross sectional area of the corresponding first section. ## Claims ### Claim 1 A journal pin comprising: a generally cylindrical body disposed about an axis, the body having a supply passage; at least one chamber disposed in the generally cylindrical body in fluid communication with the supply passage; and a recess on an outer diameter of the cylindrical body in fluid communication with the at least one chamber, wherein the at least one chamber is radially outward of the supply passage and includes an outlet to the recess, wherein a ratio of an axial length of the recess to an axial length of the body is less than about 0.5:1. ### Claim 2 (depends on 1) The journal pin of claim 1, wherein the at least one chamber has a first section radially inward of a second section, wherein a cross sectional area of the second section is greater than a cross sectional area of the corresponding first section. ### Claim 3 (depends on 1) The journal pin of claim 1, wherein a ratio of a radial depth of the recess to a radius of the cylindrical body is between 0.02:1 and 0.05:1. ### Claim 4 (depends on 1) The journal pin of claim 1, wherein a first axial end and second axial end of the recess are tapered. ### Claim 5 (depends on 4) The journal pin of claim 4, wherein the taper of each of the first axial end and second axial end of the recess is at an angle between 40° and 50°. ### Claim 6 (depends on 1) The journal pin of claim 1, wherein the at least one chamber includes a first chamber and a second chamber. ### Claim 7 (depends on 6) The journal pin of claim 6, wherein the first chamber and the second chamber are symmetrically aligned relative to the axial ends of the recess. ### Claim 8 (depends on 6) The journal pin of claim 6, wherein the first chamber and the second chamber are non-symmetrically aligned relative to the axial ends of the recess. ### Claim 9 A turbomachine epicyclic gear system comprising: a sun gear rotatable around an axis; a ring gear radially outward of the sun gear; a plurality of intermediate gears meshed with the sun gear and the ring gear; and a plurality of journal pins each configured to support one of the plurality of intermediate gears, at least one of the plurality of journal pins has a generally cylindrical body disposed about an axis, wherein the body has a supply passage in fluid communication with a recess disposed on the outer circumference of the journal pin through at least one chamber disposed in the journal pin, wherein the at least one chamber is radially outward of the supply passage and has an outlet to the recess, wherein a ratio of an axial length of the recess to an axial length of the body is less than about 0.5:1. ### Claim 10 (depends on 9) The turbomachine epicyclic gear system of claim 9, wherein each of the at least one chamber has a first section radially inward of a second section, wherein a cross sectional area of the second section is greater than a cross sectional area of the corresponding first section. ### Claim 11 (depends on 10) The turbomachine epicyclic gear system of claim 10, wherein the cross sectional area of the second section is at least 100 times the cross sectional area of the first section. ### Claim 12 (depends on 9) The turbomachine epicyclic gear system of claim 9, wherein each journal pin has a load plane circumferentially aligned with a normal load applied to the journal pins, wherein the normal load is perpendicular to the axis. ### Claim 13 (depends on 9) The turbomachine epicyclic gear system of claim 9, wherein the at least one chamber comprises a first chamber and a second chamber. ### Claim 14 (depends on 13) The turbomachine epicyclic gear system of claim 13, wherein a center of the first chamber and a center of the second chamber are between 95° and 110° circumferentially offset from the load plane. ### Claim 15 (depends on 9) The turbomachine epicyclic gear system of claim 9, wherein the epicyclic gear system includes five intermediate gears circumferentially spaced equally about the sun gear. ### Claim 16 (depends on 9) The turbomachine epicyclic gear system of claim 9, wherein each journal pin attaches the corresponding intermediate gear to a carrier, the corresponding intermediate gear configured to rotate relative to the journal pin. ### Claim 17 (depends on 9) The turbomachine epicyclic gear system of claim 9, wherein the sun gear is rotatably driven by a low speed spool. ### Claim 18 A method for assembling an epicyclic gear system in a turbomachine comprising: supporting a first intermediate gear with a journal pin having a supply passage in fluid communication with a recess through at least one chamber disposed in the journal pin, wherein the at least one chamber is radially outward of the supply passage, wherein a ratio of an axial length of the recess to an axial length of the body is less than about 0.5:1; and orienting the journal pin such that the recess is circumferentially offset from a load plane of the journal pin. ### Claim 19 (depends on 18) The method of claim 18, wherein the at least one chamber has a first section radially inward of a second section, wherein a cross sectional area of the second section is greater than a cross sectional area of the corresponding first section. ### Claim 20 (depends on 19) The method of claim 19, wherein the at least one chamber is a first chamber and a second chamber. ### Claim 21 A method of designing an epicyclic gear system for a turbomachine comprising: configuring a ring gear radially outward of a sun gear; configuring at least one intermediate gear for meshed engagement with the sun gear and the ring gear; and defining a plurality of journal pins to support a corresponding plurality of intermediate gears, at least one of the journal pins to have a generally cylindrical body disposed about an axis, wherein the body has a supply passage configured to be in fluid communication with a recess disposed on the outer circumference of the journal pin through at least one chamber disposed in the journal pin, wherein the at least one chamber is radially outward of the supply passage and has an outlet to the recess, wherein a ratio of an axial length of the recess to an axial length of the body is less than about 0.5:1. ### Claim 22 (depends on 21) The method of claim 21, wherein the at least one chamber comprises a first chamber and a second chamber. ### Claim 23 (depends on 21) The method of claim 21, including configuring each journal pin to support the corresponding intermediate gear with a carrier; and configuring the corresponding intermediate gear to rotate relative to the journal pin. ### Claim 24 (depends on 21) The method of claim 21, wherein a ratio of a radial depth of the recess to a radius of the cylindrical body is between 0.02:1 and 0.05:1.