# US 2019/0169988 A1 · Sealing device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0169988 A1 - Document ID: US20190169988A1 - Status: Published application - Kind: A1 - Application number: 16/321,117 - Filed: 2017-07-19 - Published: 2019-06-06 - Earliest claimed: 2016-08-02 - Assignees: Eagle Industry Co., Ltd. - Applicants: Eagle Industry Co., Ltd. - Inventors: Yuichiro TOKUNAGA; Masatoshi ITADANI; Akira YOSHINO - Web page: https://patentgrep.com/patent/US20190169988A1 ## CPC - F01C 19/12: for other than working fluid - F01C 1/22: of internal-axis type with equidirectional movement of co-operating members at the points of engagement, or with one of the co-operating members being stationary, the inner member having more teeth or tooth- equivalents than the outer member - F01C 19/08: Axially-movable sealings for working fluids - F02B 53/00: Internal-combustion aspects of rotary-piston or oscillating-piston engines (internal-combustion aspects of rotary pistons or outer members for co-operation therewith F02B55/00) - F02B 55/02: Pistons - F16J 15/34: with slip-ring pressed against a more or less radial face on one member - F16J 15/3412: {with cavities (F16J15/3424 takes precedence)} - Y02T 10/12: Improving ICE efficiencies - F01C: ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES (internal-combustion aspects F02B53/00, F02B55/00) - F02B: INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL (gas-turbine plants F02C; hot-gas or combustion-product positive-displacement engine plants F02G) - F16J: PISTONS {(specially adapted for dampers F16F9/32)}; CYLINDERS; SEALINGS - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract An oil seal member is provided at an outside surface of a member performing whirling motion such as a rotary engine rotor. A sliding face of the oil seal member that slides relatively to a stationary-side member is provided with a step extending circumferentially, and has a relatively high surface formed on one radial side with respect to the step and a relatively low surface on the other radial side. The high surface is provided with pumping grooves to pump oil tending to leak from the high surface side into the low surface side, into the high surface side by sliding relatively to the stationary-side member. ## Claims ### Claim 1 A sealing device that seals a gap between an outside surface of a member performing whirling motion such as a rotary engine rotor and a stationary-side member, the device comprising: an oil seal member provided at the outside surface of the member performing whirling motion, the oil seal member having a sliding face that slides relatively to the stationary-side member, the sliding face being provided with a step extending circumferentially, and having a relatively high surface formed on one radial side with respect to the step and a relatively low surface on the other radial side, the high surface being provided with pumping grooves to pump oil tending to leak from the high surface side into the low surface side, into the high surface side by sliding relatively to the stationary-side member. ### Claim 2 (depends on 1) The sealing device according to claim 1, wherein the step is provided circumferentially continuously. ### Claim 3 (depends on 1) The sealing device according to claim 1, wherein the step is provided circumferentially intermittently, and a portion not provided with the step is provided with a dam formed by the high surface protruding to the low surface side. ### Claim 4 (depends on 3) The sealing device according to claim 3, wherein the dam is provided at an angle from the low surface side to the high surface side so that the high surface side is located downstream. ### Claim 5 (depends on 1) The sealing device according to claim 1, wherein the pumping grooves are provided circumferentially independently, an upstream cavitation formation region of each pumping groove is disposed radially close to the low surface side and a downstream positive pressure generation region is disposed close to a side opposite to the low surface side, and fluid drawn in from the low surface side at the cavitation formation region of each pumping groove passes through the pumping groove and is returned from the positive pressure generation region to the side opposite to the low surface side. ### Claim 6 (depends on 2) The sealing device according to claim 2, wherein the pumping grooves are provided circumferentially independently, an upstream cavitation formation region of each pumping groove is disposed radially close to the low surface side and a downstream positive pressure generation region is disposed close to a side opposite to the low surface side, and fluid drawn in from the low surface side at the cavitation formation region of each pumping groove passes through the pumping groove and is returned from the positive pressure generation region to the side opposite to the low surface side. ### Claim 7 (depends on 3) The sealing device according to claim 3, wherein the pumping grooves are provided circumferentially independently, an upstream cavitation formation region of each pumping groove is disposed radially close to the low surface side and a downstream positive pressure generation region is disposed close to a side opposite to the low surface side, and fluid drawn in from the low surface side at the cavitation formation region of each pumping groove passes through the pumping groove and is returned from the positive pressure generation region to the side opposite to the low surface side. ### Claim 8 (depends on 4) The sealing device according to claim 4, wherein the pumping grooves are provided circumferentially independently, an upstream cavitation formation region of each pumping groove is disposed radially close to the low surface side and a downstream positive pressure generation region is disposed close to a side opposite to the low surface side, and fluid drawn in from the low surface side at the cavitation formation region of each pumping groove passes through the pumping groove and is returned from the positive pressure generation region to the side opposite to the low surface side.