# US 2014/0191690 A1 · Construction machine and method of controlling turning electric motor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0191690 A1 - Document ID: US20140191690A1 - Status: Published application - Kind: A1 - Application number: 14/205,590 - Filed: 2014-03-12 - Published: 2014-07-10 - Earliest claimed: 2011-09-15 - Assignees: Sumitomo Heavy Industries, Ltd. - Applicants: Sumitomo Heavy Industries, Ltd. - Inventors: Makoto YANAGISAWA - Web page: https://patentgrep.com/patent/US20140191690A1 ## CPC - B60L 50/15: with additional electric power supply (with capacitors charged by engine-driven generators B60L50/40; with batteries charged by engine-driven generators B60L50/61) - B60L 1/003: {to auxiliary motors, e.g. for pumps, compressors} - E02F 9/128: {Braking systems} - E02F 9/2095: {Control of electric, electro-mechanical or mechanical equipment not otherwise provided for, e.g. ventilators, electro-driven fans (control of hydraulic driven equipment E02F9/22)} - B60L 2200/40: Working vehicles - Y02T 10/7072: Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors - B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES - E02F: DREDGING; SOIL-SHIFTING (winning peat E21C49/00) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A construction machine includes a turning electric motor configured to drive a turning mechanism configured to cause an upper-part turning body to turn relative to a lower-part traveling body and a control unit configured to control driving of the turning electric motor. The control unit is configured to cause the output of the turning electric motor to continue after the turning speed of the upper-part turning body becomes zero, based on the magnitude of the output or the direction of the output of the turning electric motor at the time when the upper-part turning body is decelerated and its turning speed becomes zero. ## Claims ### Claim 1 A construction machine, comprising: a turning electric motor configured to drive a turning mechanism configured to cause an upper-part turning body to turn relative to a lower-part traveling body; and a control unit configured to control driving of the turning electric motor, wherein the control unit is configured to cause an output of the turning electric motor to continue after a turning speed of the upper-part turning body becomes zero, based on a magnitude of the output or a direction of the output of the turning electric motor at a time when the upper-part turning body is decelerated and the turning speed thereof becomes zero. ### Claim 2 (depends on 1) The construction machine as claimed in claim 1, wherein the control unit is configured to cause the output of the turning electric motor to continue when a direction of a torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is equal to a direction in which the upper-part turning body has turned. ### Claim 3 (depends on 2) The construction machine as claimed in claim 2, wherein the control unit is configured to cause the output of the turning electric motor to be zero or reduced when an absolute value of a torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is less than a predetermined value. ### Claim 4 (depends on 3) The construction machine as claimed in claim 3, wherein the control unit is configured to control the output of the turning electric motor by proportional integral control, and wherein the control unit is configured to reset an integral component in the proportional integral control to zero when the absolute value of the torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is less than the predetermined value. ### Claim 5 (depends on 1) The construction machine as claimed in claim 1, wherein the control unit is configured to cause the output of the turning electric motor to continue when a magnitude of a torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is greater than or equal to a predetermined value. ### Claim 6 (depends on 5) The construction machine as claimed in claim 5, wherein the control unit is configured to cause the output of the turning electric motor to be zero or reduced when an absolute value of a torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is less than a predetermined value. ### Claim 7 (depends on 6) The construction machine as claimed in claim 6, wherein the control unit is configured to control the output of the turning electric motor by proportional integral control, and wherein the control unit is configured to reset an integral component in the proportional integral control to zero when the absolute value of the torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is less than the predetermined value. ### Claim 8 A method of controlling a turning electric motor configured to drive a turning mechanism configured to turn an upper-part turning body relative to a lower-part traveling body, comprising: causing the upper-part turning body to turn relative to the lower-part traveling body by driving the turning electric motor to rotate in a first direction; decelerating the upper-part turning body by driving the turning electric motor to rotate in a second direction reverse to the first direction; and causing an output of the turning electric motor to continue after a turning speed of the upper-part turning body becomes zero, based on a magnitude of the output or a direction of the output of the turning electric motor at a time when the upper-part turning body is decelerated and the turning speed thereof becomes zero. ### Claim 9 (depends on 8) The method of controlling a turning electric motor as claimed in claim 8, wherein the output of the turning electric motor is caused to continue when a direction of a torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is equal to a direction in which the upper-part turning body has turned. ### Claim 10 (depends on 9) The method of controlling a turning electric motor as claimed in claim 9, wherein the output of the turning electric motor is caused to be zero or reduced when an absolute value of a torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is less than a predetermined value. ### Claim 11 (depends on 10) The method of controlling a turning electric motor as claimed in claim 10, wherein the output of the turning electric motor is controlled by proportional integral control, and wherein an integral component in the proportional integral control is reset to zero when the absolute value of the torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is less than the predetermined value. ### Claim 12 (depends on 8) The method of controlling a turning electric motor as claimed in claim 8, wherein the output of the turning electric motor is caused to continue when a magnitude of a torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is greater than or equal to a predetermined value. ### Claim 13 (depends on 12) The method of controlling a turning electric motor as claimed in claim 12, wherein the output of the turning electric motor is caused to be zero or reduced when an absolute value of a torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is less than a predetermined value. ### Claim 14 (depends on 13) The method of controlling a turning electric motor as claimed in claim 13, wherein the output of the turning electric motor is controlled by proportional integral control, and wherein an integral component in the proportional integral control is reset to zero when the absolute value of the torque output by the turning electric motor when the turning speed of the upper-part turning body becomes zero is less than the predetermined value.