# US 2018/0320693 A1 · Coolant pump for an internal combustion engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0320693 A1 - Document ID: US20180320693A1 - Status: Published application - Kind: A1 - Application number: 15/772,814 - Filed: 2016-10-19 - Published: 2018-11-08 - Earliest claimed: 2015-11-06 - Assignees: Pierburg GmbH - Applicants: Pierburg GmbH - Inventors: STEPHAN ZIELBERG; MICHAEL-THOMAS BENRA; ANDREAS BURGER; MARTIN NOWAK; STEFAN ROTHGANG - Web page: https://patentgrep.com/patent/US20180320693A1 ## CPC - F04D 15/0038: {by varying the effective cross-sectional area of flow through the rotor} - F01P 5/10: Pumping liquid coolant; Arrangements of coolant pumps - F04D 13/12: Combinations of two or more pumps (combinations with priming pumps or booster pumps to counteract vapour-lock F04D9/04) - F01P 2005/105: {Using two or more pumps} - F05D 2270/64: Hydraulic actuators - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - F01P: COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES (arrangements in connection with cooling of propulsion units in vehicles B60K11/00; heat-transfer, heat-exchange or heat-storage materials C09K5/00; {cooling of gas-turbine engines F02C7/12}; heat exchange in general, radiators F28) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract A coolant pump for an internal combustion engine. The coolant pump includes a delivery duct, a drive shaft, a coolant pump impeller arranged on the drive shaft to rotate therewith and to convey a coolant, and an adjustable control slide which controls a throughflow cross-section of an annular gap arranged between an outlet of the coolant pump impeller and the surrounding delivery duct. The control slide comprises a first pressure chamber arranged on a side of the control slide facing away from the coolant pump impeller and a second pressure chamber arranged opposite thereto. A control pump includes a control pump impeller arranged at the drive shaft to rotate therewith. A connecting duct fluidically connects the flow duct to the second pressure chamber. A pressure duct fluidically connects the flow duct outlet to the first pressure chamber. A valve opens and closes a throughflow cross-section of the pressure duct. ## Claims ### Claim at position 1 1-10. (canceled) ### Claim 11 A coolant pump for an internal combustion engine, the coolant pump comprising: a delivery duct; a drive shaft; a coolant pump impeller arranged on the drive shaft so as to rotate jointly therewith, the coolant pump impeller being configured to convey a coolant; a control slide which is configured to be adjustable so as to control a throughflow cross-section of an annular gap arranged between an outlet of the coolant pump impeller and the surrounding delivery duct, the control slide comprising a first pressure chamber arranged on a first axial side of the control slide facing away from the coolant pump impeller and a second pressure chamber arranged on a second axial side of the control slide facing the coolant pump impeller; a connecting duct; a control pump comprising a control pump impeller which is arranged at the drive shaft so as to rotate jointly therewith, and a flow duct which is configured so that a pressure can be generated by a rotation of the control pump impeller, the flow duct comprising an outlet and being fluidically connected via the connecting duct to the second pressure chamber; a pressure duct configured to fluidically connect the outlet of the flow duct to the first pressure chamber of the control slide; and a valve configured to open and to close a throughflow cross-section of the pressure duct. ### Claim 12 (depends on 11) The coolant pump as recited in claim 11, wherein the valve is a 3/2-way magnetic valve. ### Claim 13 (depends on 11) The coolant pump as recited in claim 11, wherein the control pump impeller is integrally formed with the coolant pump impeller. ### Claim 14 (depends on 11) The coolant pump as recited in claim 11, further comprising: a first housing part configured to be fixed, wherein, the flow duct of the control pump is arranged in the first housing part, and the second pressure chamber is arranged on a side of the first housing part which is axially opposite to the flow duct. ### Claim 15 (depends on 14) The coolant pump as recited in claim 14, wherein the connecting duct is arranged in the first housing part. ### Claim 16 (depends on 14) The coolant pump as recited in claim 14, further comprising: a second housing part, wherein, the pressure duct is further configured to extend from the outlet of the flow duct of the control pump through the first housing part and the second housing part into the first pressure chamber, and the throughflow cross-section which is opened and closed by the valve is arranged in the second housing part. ### Claim 17 (depends on 16) The coolant pump as recited in claim 16, wherein, the pressure duct in the first housing part is formed radially inside the control slide, and the first housing part delimits the first pressure chamber and the second pressure chamber radially inwards. ### Claim 18 (depends on 11) The coolant pump as recited in claim 11, wherein, the control pump further comprises an inlet, and the connecting duct is arranged to extend from an area of the inlet of the control pump into the second pressure chamber. ### Claim 19 (depends on 11) The coolant pump as recited in claim 11, wherein, the coolant pump impeller comprises a rear side, and the control pump impeller is arranged on the rear side of the coolant pump impeller axially between the second pressure chamber and the coolant pump impeller. ### Claim 20 (depends on 11) The coolant pump as recited in claim 11, wherein the control pump is a side channel pump.