# US 2021/0340903 A1 · Work machine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0340903 A1 - Document ID: US20210340903A1 - Status: Published application - Kind: A1 - Application number: 17/271,302 - Filed: 2018-09-06 - Published: 2021-11-04 - Earliest claimed: 2018-09-06 - Assignees: Honda Motor Co., Ltd. - Applicants: Honda Motor Co., Ltd. - Inventors: Hiroaki Kojima; Masashi Kai; Jun Yamamoto; Mitsuhiro Ito - Web page: https://patentgrep.com/patent/US20210340903A1 ## CPC - F02B 63/048: {Portable engine-generator combinations} - F02B 63/044: {the engine-generator unit being placed on a frame or in an housing} - F02M 37/0082: {Devices inside the fuel tank other than fuel pumps or filters (electrical pumps submerged in fuel tanks F02M37/10, jet pumps F02M37/025)} - F02B 2063/045: {Frames for generator-engine sets} - F02B: INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL (gas-turbine plants F02C; hot-gas or combustion-product positive-displacement engine plants F02G) - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF ## Abstract A pressure variation in a fuel tank can be prevented, and leakage of liquid fuel can be prevented even if the fuel tank is inclined in a predetermined direction, without operation for opening and closing a breather passage. An engine generator includes: a first breather passage having an opening at a position above a liquid fuel in a tank bulge section when the engine generator is inclined to the right (corresponding to a first direction); and a second breather passage having an opening at a position above the liquid fuel in the tank bulge section when the engine generator is inclined in the left direction (a second direction). ## Claims ### Claim 1 A work machine, comprising a fuel tank for storing liquid fuel, wherein the fuel tank has a tank shape and includes: a fuel supply port; and a tank bulge section that bulges to a position higher than the fuel supply port, the tank bulge section being formed, at an intermediate position in a front-rear direction of the fuel tank, so as to have a cross section in which a front-rear length decreases to the upper side, wherein the fuel tank comprises a breather passage through which an inside and an outside of the tank bulge section communicate with each other, and wherein the breather passage comprises: a first breather passage having an opening at a position above the liquid fuel in the tank bulge section when the work machine is inclined in a first direction, the first direction being one of left and right directions, the position of the first breather passage opening being intermediate in the front-rear direction of the fuel tank, the first breather passage being routed so as to include a position above the liquid fuel when the work machine is inclined in a second direction, the second direction being the other of the left and right directions; and a second breather passage having an opening at a position above the liquid fuel in the tank bulge section when the work machine is inclined in the second direction, the position of the second breather passage opening being intermediate in the front-rear direction of the fuel tank, the second breather passage being routed so as to include a position above the liquid fuel when the work machine is inclined in the first direction. ### Claim 2 (depends on 1) The work machine according to claim 1, wherein a V-shaped cross section of the tank bulge section extends over a width direction of the fuel tank. ### Claim 3 (depends on 1) The work machine according to claim 1, wherein the first breather passage extends from the opening of the first breather passage along the first direction and then extends downward along a side wall of the fuel tank, and wherein the second breather passage extends from the opening of the second breather passage along the second direction, then turns back to extend along the first direction, and then extends downward along the side wall of the fuel tank. ### Claim 4 (depends on 1) The work machine according to claim 1, wherein the first and second breather passages have a downward slope toward the opening of the first breather passage and the opening of the second breather passage, respectively. ### Claim 5 (depends on 1) The work machine according to claim 1, wherein the first and second breather passages are arranged in the fuel tank, exit from a predetermined position in the fuel tank, and subsequently are connected to a canister or an air cleaner case. ### Claim 6 (depends on 1) The work machine according to claim 1, wherein a portion of the first breather passage except for the opening of the first breather passage and a portion of the second breather passage except for the opening of the second breather passage are arranged outside the fuel tank, and the first and second breather passages are connected to a canister or an air cleaner case. ### Claim 7 (depends on 1) The work machine according to claim 1, wherein the fuel tank has a wave protection member arranged around the opening of the first breather passage and the opening of the second breather passage in the fuel tank to enable preventing a wave of the liquid fuel from getting into the opening of the first breather passage and the opening of the second breather passage. ### Claim 8 (depends on 1) The work machine according to claim 1, wherein the work machine is a portable type generator that uses the liquid fuel in the fuel tank to generate electricity, and a left-right length of the work machine is shorter than a front-rear length of the work machine.