# US 10,371,109 B2 · High-pressure fuel supply pump > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,109 B2 - Document ID: US10371109B2 - Status: Granted - Kind: B2 - Application number: 15/105,973 - Filed: 2014-11-17 - Published: 2016-10-27 - Granted: 2019-08-06 - Earliest claimed: 2013-12-27 - Assignees: Hitachi Automotive Systems, Ltd. - Applicants: Hitachi Automotive Systems, Ltd. - Inventors: Yuta Saso; Atsuji Saito; Satoshi Usui; Shingo Tamura; Moritsugu Akiyama; Hiroyuki Yamada; Atsushi Hohkita - Web page: https://patentgrep.com/patent/US10371109B2 ## CPC - F02M 59/447: {means specially adapted to limit fuel delivery or to supply excess of fuel temporarily, e.g. for starting of the engine (combined with fuel pump regulating devices F02D)} - F02M 59/44: Details, components parts, or accessories not provided for in, or of interest apart from, the apparatus of groups F02M59/02 - F02M59/42; {Pumps having transducers, e.g. to measure displacement of pump rack or piston} - F02M 59/46: Valves - F02M 59/48: Assembling; Disassembling; Replacing - F04B 1/0452: Distribution members, e.g. valves (machines or pumps with cam-actuated distribution members at the outer ends of the cylinders F04B1/0472; machines or pumps with cam-actuated distribution members at the inner ends of the cylinders F04B1/0531; the piston-driving cams being provided with inlets and outlets F04B1/0535) - F04B 49/035: Bypassing - F04B 49/24: Bypassing - F04B 53/16: Casings; Cylinders; Cylinder liners or heads; Fluid connections - F04B 53/22: Arrangements for enabling ready assembly or disassembly - F02M 59/025: {characterised by a single piston} - F02M 59/368: {Pump inlet valves being closed when actuated} - F02M 59/462: {Delivery valves} - F02M 2200/8061: involving press-fit, i.e. interference or friction fit - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF - F04B: POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS (machines for liquids, or pumps, of rotary-piston or oscillating-piston type F04C; non-positive-displacement pumps F04D; pumping of fluid by direct contact of another fluid or by using inertia of fluid to be pumped F04F) ## Abstract A high-pressure fuel supply pump in which a relief valve mechanism is not detached by a force generated by a differential pressure between an inlet side and an output side of a relief valve mechanism is obtained. According to the present invention, in order to obtain the high-pressure fuel supply pump, the relief valve mechanism of the high-pressure fuel supply pump is oriented from a downstream side of a discharge valve to an upstream side of the discharge valve, and the output side of the relief valve mechanism is inserted from the upstream side of the discharge valve into the pump housing, and the relief valve mechanism is fixed with press fitting. Therefore, a force exerted by the differential pressure between the inlet side pressure and the output side pressure of the relief valve mechanism is exerted in a direction in which the relief valve mechanism is inserted, so that the relief valve mechanism can be prevented from being detached. ## Claims ### Claim 1 A high-pressure fuel supply pump comprising: an electromagnetically driven intake valve mechanism that includes an electromagnetically driven plunger rod; a pump housing formed with a discharge path in communication with a compression chamber; a discharge valve arranged in the discharge path; a discharge port discharging the fuel to an insertion port of a relief valve mechanism, the insertion port being provided in the pump housing; and the relief valve mechanism allows a fuel to be in communication from a downstream side of the discharge valve to an upstream side of the discharge valve by opening the relief valve mechanism when a pressure difference between an inlet side and an output side becomes equal to or more than a predetermined valve opening pressure, wherein the relief valve mechanism is made into a unit including a relief valve, a relief spring arranged at the upstream side of the discharge valve with respect to the relief valve and biasing the relief valve toward a downstream side of the discharge valve, a valve seat coming into contact with the relief valve when the valve is closed, and a cylindrical valve housing enclosing the relief valve, and the relief valve mechanism is inserted into the pump housing in a direction opposite to a direction in which the relief spring biases the relief valve, wherein a longitudinal axis of the electromagnetically driven plunger rod is coincident with a longitudinal axis of the discharge path, and the discharge port is arranged on a same axis as the relief valve of the relief valve mechanism. ### Claim 2 (depends on 1) The high-pressure fuel supply pump according to claim 1, wherein the pump housing is formed with a stopper that comes into contact with the valve housing in an insertion direction of the relief valve mechanism. ### Claim 3 (depends on 1) The high-pressure fuel supply pump according to claim 1, wherein an outer peripheral surface of the valve housing is formed with a press fitting unit enlarged in an external diameter as compared with an inlet side of the relief valve mechanism. ### Claim 4 (depends on 3) The high-pressure fuel supply pump according to claim 3, wherein the pump housing is formed with a stopper that comes into contact with the valve housing in an insertion direction of the relief valve mechanism, and the stopper is formed at an upstream side of the discharge valve with respect to the press fitting unit. ### Claim 5 (depends on 1) The high-pressure fuel supply pump according to claim 1, wherein the valve seat is integrally formed with the valve housing. ### Claim 6 (depends on 1) The high-pressure fuel supply pump according to claim 1, wherein the relief valve mechanism has a relief spring adjuster that is press-fitted in the valve housing and that comes into contact with the relief spring. ### Claim 7 (depends on 6) The high-pressure fuel supply pump according to claim 6, wherein the relief spring adjuster is formed with a relief path through which the fuel passes. ### Claim 8 (depends on 1) The high-pressure fuel supply pump according to claim 1, comprising a seal portion for sealing an insertion port of the relief valve mechanism, the insertion port being provided in the pump housing. ### Claim 9 (depends on 1) The high-pressure fuel supply pump according to claim 1, wherein a center axis of the relief valve mechanism is in a same plane as a center axis of the discharge valve. ### Claim 10 (depends on 1) The high-pressure fuel supply pump according to claim 1, wherein the relief valve mechanism is in communication with an intake path, wherein an output side of the intake path delivers the fuel to the compression chamber. ### Claim 11 (depends on 1) The high-pressure fuel supply pump according to claim 1, wherein an output side of the relief valve mechanism is in communication with the compression chamber.