# US 2014/0150640 A1 · Hydrostatic Positive Displacement Machine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150640 A1 - Document ID: US20140150640A1 - Status: Published application - Kind: A1 - Application number: 13/910,258 - Filed: 2013-06-05 - Published: 2014-06-05 - Earliest claimed: 2012-06-06 - Assignees: Linde Hydraulics GmbH & Co. KG - Applicants: Linde Hydraulics GmbH & Co. KG - Inventors: Richard Hofmann; Martin Bergmann - Web page: https://patentgrep.com/patent/US20140150640A1 ## CPC - F01B 3/0035: {having two or more sets of cylinders or pistons} - F04B 1/2021: characterised by the contact area between cylinder barrel and valve plate - F04B 1/2042: Valves - F04B 1/306: by turning the swash plate, e.g. with fixed inclination - F01B: MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES (of rotary-piston or oscillating-piston type F01C; of non-positive-displacement type F01D; internal-combustion engines F02B; combustion-product engine plants F02G; machines or engines, other than of positive-displacement type, for liquids F03B; positive-displacement engines driven by liquids F03C; wind motors F03D; positive-displacement machines for liquids F04B; rotary-piston, or oscillating-piston, positive-displacement machines for liquids F04C) - 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 hydrostatic positive displacement machine has a cylinder drum (4) located in a housing (9) and rotatable around an axis of rotation (2). During rotation of the cylinder drum (4), a piston bore (5) is placed in alternating communication with an inlet side (E) and an outlet side (A). The inlet side (E) and outlet side (A) comprise connections (21; 22) to a control plate (12). A reversing device (30) is located in a reversing area (25; 26) between the connections (21, 22) on the control plate (12). The reversing device (30) damps the pressure adjustment between a displacement chamber (V) and the pressure present in the connection (21; 22). The reversing device (30) includes at least two flow connections which are actuated simultaneously by the displacement chamber (V) as it moves along the reversing area (25; 26). ## Claims ### Claim 1 A hydrostatic positive displacement machine, comprising: a cylinder drum located in a housing and rotatable around an axis of rotation, wherein the cylinder drum is provided with at least one piston bore; a longitudinally displaceable piston located in the piston bore, wherein during rotation of the cylinder drum the piston bore is placed in alternating communication with an inlet side and an outlet side, wherein the inlet side and outlet side comprise connections to a control plate; and a reversing device located in a reversing area between the connections on the control plate and which, by means of a volume flow into or out of a displacement chamber formed by the piston and the piston bore, damps a pressure adjustment between the displacement chamber and a pressure present in the connection, wherein the reversing device comprises at least two flow connections which are actuated simultaneously by the displacement chamber as it moves along the reversing area. ### Claim 2 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the flow connections on the control plate are located on a contour line which corresponds to a leading edge of a connecting opening of the displacement chamber. ### Claim 3 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the flow connections are located on different reference diameters on the control plate in a radial direction such that the displacement chamber, as it moves along the control plate, opens the flow connections simultaneously with a leading edge of a connecting opening of the displacement chamber. ### Claim 4 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the reversing device includes at least one additional flow connection, wherein the flow connections are arranged one after another in a direction of movement of the displacement chamber. ### Claim 5 (depends on 4) The hydrostatic positive displacement machine as recited in claim 4, wherein the flow connections are distributed on the control plate in a peripheral direction and in a radial direction so that the displacement chamber, as it moves along the control plate, opens at least two flow connections simultaneously and at least one additional flow opening after a delay. ### Claim 6 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the flow connections are each in the form of a nozzle bore. ### Claim 7 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the flow connections are each in the form of a throttle notch. ### Claim 8 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1 wherein the flow connections are selected from the group consisting of nozzle bores and throttle notches and the flow connections are formed in the control plate. ### Claim 9 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the reversing device is a screen-like or grid-like structure with a plurality of pores, wherein each of the pores forms a flow connection. ### Claim 10 (depends on 9) The hydrostatic positive displacement machine as recited in claim 9, wherein the screen-like or grid-like structure is a mesh fabric. ### Claim 11 (depends on 9) The hydrostatic positive displacement machine as recited in claim 9, wherein the screen-like or grid-like structure is a plate or sheet provided with perforations. ### Claim 12 (depends on 9) The hydrostatic positive displacement machine as recited in claim 9, wherein a plurality of screen-like or grid-like structures are arranged one behind the other in the direction of flow of the reversing device. ### Claim 13 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the reversing device comprises a high-porosity material with a plurality of pores, wherein each of the pores forms a flow connection. ### Claim 14 (depends on 13) The hydrostatic positive displacement machine as recited in claim 13, wherein the high-porosity material comprises an open-pore metal foam. ### Claim 15 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the reversing device is selected from the group consisting of a screen, a grid, and a high-porosity material and the reversing device is an insert which is located in a boring of the control plate. ### Claim 16 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the flow connections are in communication with the inlet side. ### Claim 17 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the flow connections are in communication with the outlet side. ### Claim 18 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the flow connections are in communication with a hydraulic buffer. ### Claim 19 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the positive displacement machine is an axial piston machine. ### Claim 20 (depends on 1) The hydrostatic positive displacement machine as recited in claim 1, wherein the positive displacement machine is selected from a pump or motor.