# US 10,502,213 B2 · Electronically-controlled compressed air system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,502,213 B2 - Document ID: US10502213B2 - Status: Granted - Kind: B2 - Application number: 15/379,881 - Filed: 2016-12-15 - Published: 2018-06-21 - Granted: 2019-12-10 - Earliest claimed: 2016-12-15 - Assignees: Caterpillar Global Mining Equipment LLC - Applicants: Caterpillar Global Mining Equipment LLC - Inventors: Rick William Berlage; Brian Daniel Rockwood; Jerry E. Berkeland - Web page: https://patentgrep.com/patent/US10502213B2 ## CPC - F04C 29/124: {with inlet and outlet valves specially adapted for rotary or oscillating piston pumps} - F04B 23/00: Pumping installations or systems (pumps characterised by combination with, or adaptation to, specific driving engines or motors F04B17/00) - F04B 23/02: having reservoirs - F04B 41/02: having reservoirs - F04C 18/16: with helical teeth, e.g. chevron-shaped, screw type {(for non-parallel axes of movement F04C18/48)} - F04C 23/02: Pumps characterised by combination with, or adaptation to, specific driving engines or motors - F04C 28/24: characterised by using valves controlling pressure or flow rate, e.g. discharge valves {or unloading valves}(F04C28/10 takes precedence) - F04C 29/0085: {Prime movers} - F04D 15/0083: {Protection against sudden pressure change, e.g. check valves} - F15B 13/024: {Pressure relief valves} - F15B 2211/40515: with variable throttles or orifices - F15B 2211/50518: using pressure relief valves - Y10T 137/7761: Electrically actuated valve - F04C: ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS (engines F03C); ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS - 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) - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - F15B: SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A compressed air system may comprise an air compressor configured to generate compressed air, a reservoir configured to store the compressed air, a reservoir pressure sensor configured to monitor an actual reservoir pressure of the compressed air stored in the reservoir, an outlet valve configured to regulate a flow of the compressed air out of the reservoir, and an outlet electronic actuator configured to adjust a position of the outlet valve. The compressed air system may further comprise an electronic control module (ECM) configured to transmit a command to the outlet electronic actuator to cause the outlet electronic actuator to open the outlet valve when the actual reservoir pressure is above a target reservoir pressure, and transmit a command to the electronic actuator to cause the electronic actuator to close the outlet valve when the actual reservoir pressure is below the target reservoir pressure. ## Claims ### Claim 1 A compressed air system for a machine, the compressed air system comprising: an air compressor configured to generate compressed air; a reservoir configured to store the compressed air generated by the air compressor; a reservoir pressure sensor configured to monitor an actual reservoir pressure of the compressed air stored in the reservoir; an outlet valve configured to variably regulate a flow of the compressed air out of the reservoir, wherein the outlet valve is a butterfly valve; an outlet electronic actuator operatively associated with the outlet valve to adjust a position of the outlet valve; and an electronic control module (ECM) in electronic communication with the reservoir pressure sensor and the outlet electronic actuator, the ECM being configured to: transmit a command to the outlet electronic actuator to cause the outlet electronic actuator to at least partially open the outlet valve when the actual reservoir pressure is above a target reservoir pressure, transmit a command to the outlet electronic actuator to cause the electronic actuator to close the outlet valve when the actual reservoir pressure is below the target reservoir pressure; and wherein the butterfly valve is configured to permit leakage of compressed air when the butterfly valve is closed. ### Claim 2 (depends on 1) The compressed air system of claim 1, wherein the ECM is further configured to transmit a command to the outlet electronic actuator to cause the outlet electronic actuator to close the outlet valve when the machine is turned off. ### Claim 3 (depends on 1) The compressed air system of claim 1, wherein the ECM is further configured to select zero as the target reservoir pressure when an engine of the machine is starting. ### Claim 4 (depends on 1) The compressed air system of claim 1, wherein the compressed air system further comprises: an inlet valve configured to regulate a flow of air to an inlet of the air compressor; and an inlet electronic actuator operatively associated with the inlet valve and configured to adjust a position of the inlet valve. ### Claim 5 (depends on 4) The compressed air system of claim 4, wherein the ECM is in electronic communication with the inlet electronic actuator and is further configured to: transmit a command to the inlet electronic actuator to cause the inlet electronic actuator to close the inlet valve when the actual reservoir pressure is above the target reservoir pressure; and transmit a command to the inlet electronic actuator to cause the inlet electronic actuator to at least partially open the inlet valve when the actual reservoir pressure is below the target reservoir pressure. ### Claim 6 (depends on 4) The compressed air system of claim 4, wherein the inlet valve is a butterfly valve. ### Claim 7 (depends on 4) The compressed air system of claim 4, wherein the ECM includes a proportional-integral-derivative (PID) controller configured to: transmit a positive command to the inlet electronic actuator and the outlet electronic actuator when the actual reservoir pressure is below the target reservoir pressure, the inlet electronic actuator interpreting the positive command as a command to at least partially open the inlet valve, the outlet electronic actuator interpreting the positive command as a command to close the outlet valve; and transmit a negative command to the inlet electronic actuator and the outlet electronic actuator when the actual reservoir pressure is above the target reservoir pressure, the inlet electronic actuator interpreting the negative command as a command to close the inlet valve, the outlet electronic actuator interpreting the negative command as a command to open the outlet valve. ### Claim 8 (depends on 1) The compressed air system of claim 1, wherein the compressed air, stored in the reservoir, is used to perform: at least one standby operation that is performed constantly during the operation of the machine at a fixed standby pressure; at least one fixed-pressure auxiliary operation that is performed intermittently during the operation of the machine at a fixed auxiliary pressure; and at least one variable-pressure auxiliary operation that is performed intermittently during the operation of the machine at a variable auxiliary pressure. ### Claim 9 (depends on 8) The compressed air system of claim 8, wherein the ECM is further configured to select the target reservoir pressure as a maximum out of the fixed standby pressure and the variable auxiliary pressure plus a fixed margin pressure when the at least one variable-pressure auxiliary operation is active and the fixed-pressure auxiliary operation is inactive. ### Claim 10 (depends on 8) The compressed air system of claim 8, wherein the ECM is further configured to select the target reservoir pressure as the fixed standby pressure when the at least one variable-pressure auxiliary operation and the fixed-pressure auxiliary operation are inactive. ### Claim 11 A method for electronically controlling a pressure of compressed air stored in a reservoir of a compressed air system of a machine, the reservoir including an outlet valve configured to variably regulate a flow of the compressed air out of the reservoir, the method comprising: determining a pressure difference between an actual reservoir pressure of the compressed air stored in the reservoir and a target reservoir pressure, the actual reservoir pressure being monitored by a reservoir pressure sensor; transmitting a command to an outlet electronic actuator to cause the outlet electronic actuator to at least partially open the outlet valve when the actual reservoir pressure is above the target reservoir pressure, wherein the outlet valve is a butterfly valve; transmitting a command to the outlet electronic actuator to cause the outlet electronic actuator to close the outlet valve when the actual reservoir pressure is below the target reservoir pressure; and wherein the butterfly valve is configured to permit leakage of the compressed air when the butterfly valve is closed. ### Claim 12 (depends on 11) The method of claim 11, further comprising transmitting a command to the outlet electronic actuator to cause the outlet electronic actuator to close the outlet valve when the machine is turned off, the outlet valve permitting compressed air to bleed out when closed. ### Claim 13 (depends on 11) The method of claim 11, further comprising determining the target reservoir pressure for the compressed air stored in the reservoir prior to determining the pressure difference between the actual reservoir pressure of the compressed air stored in the reservoir and the target reservoir pressure. ### Claim 14 (depends on 11) The method of claim 11, wherein the compressed air stored in the reservoir is used to perform: at least one standby operation that is performed constantly during the operation of the machine at a fixed standby pressure; at least one fixed-pressure auxiliary operation that is performed intermittently during the operation of the machine at a fixed auxiliary pressure; and at least one variable-pressure auxiliary operation that is performed intermittently during the operation of the machine at a variable auxiliary pressure. ### Claim 15 (depends on 14) The method of claim 14, wherein determining the target reservoir pressure comprises selecting the target reservoir pressure as the fixed standby pressure when the fixed-pressure auxiliary operation and the variable-pressure auxiliary operation are inactive. ### Claim 16 (depends on 14) The method of claim 14, wherein determining the target reservoir pressure comprises selecting the target reservoir pressure as a maximum out of the fixed standby pressure and the variable auxiliary pressure plus a fixed margin pressure when the variable-pressure auxiliary operation is active and the fixed-pressure auxiliary operation is inactive. ### Claim 17 (depends on 16) The method of claim 16, wherein determining the target reservoir pressure comprises selecting zero as the target reservoir pressure when an engine of the machine is starting. ### Claim 18 A machine, comprising: an internal combustion engine; an air compressor driven by the internal combustion engine and having an inlet; an inlet valve configured to regulate a flow of air into the inlet; an inlet electronic actuator configured to adjust a position of the inlet valve; a reservoir configured to store compressed air generated by the air compressor; a reservoir pressure sensor configured to monitor an actual reservoir pressure of the compressed air stored in the reservoir; an outlet valve configured to variably regulate a flow of the compressed air out of the reservoir, wherein the outlet valve is a butterfly valve; an outlet electronic actuator configured to adjust a position of the outlet valve; and an electronic control module (ECM) in electronic communication with the reservoir pressure sensor, the inlet electronic actuator, and the outlet electronic actuator, the ECM being configured to: transmit a positive command to the inlet electronic actuator and the outlet electronic actuator when the actual reservoir pressure is below a target reservoir pressure, the positive command causing the inlet electronic actuator to at least partially open the inlet valve, the positive command causing the outlet electronic actuator to close the outlet valve; transmit a negative command to the inlet electronic actuator and the outlet electronic actuator when the actual reservoir pressure is above the target reservoir pressure, the negative command causing the inlet electronic actuator to close the inlet valve, the negative command causing the outlet electronic actuator to at least partially open the outlet valve; and wherein the butterfly valve is configured to permit leakage of compressed air when the butterfly valve is closed.