# US 9,751,217 B2 · Robot hand for transporting article, robot and robot system provided with robot hand, and method for controlling robot hand > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,751,217 B2 - Document ID: US9751217B2 - Status: Granted - Kind: B2 - Application number: 14/312,811 - Filed: 2014-06-24 - Published: 2015-01-01 - Granted: 2017-09-05 - Earliest claimed: 2013-06-26 - Assignees: Fanuc Corporation - Applicants: FANUC Corporation - Inventors: Masaru Oda - Web page: https://patentgrep.com/patent/US9751217B2 ## CPC - B25J 19/002: {using counterweights} - B25J 18/02: extensible - Y10S 901/22: Fluid motor - Y10T 74/20305: Robotic arm - B25J: MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES ({manipulators specially adapted for use in surgery A61B34/70; manipulators used in cleaning hollow articles B08B9/04}; manipulators associated with rolling mills B21B39/20; manipulators associated with forging machines B21J13/10; {manipulators associated with picking-up and placing mechanisms B23P19/007}; means for holding wheels or parts thereof B60B30/00; {vehicles with ground-engaging propulsion means, e.g. walking members B62D57/02, B62D57/032; devices for picking-up and depositing articles or materials between conveyors B65G47/90, B65G47/91; manipulators with gripping or holding means for transferring packages B65H67/065}; cranes B66C; {manipulators used in the protection or supervision of pipe-line installations F17D5/00; walking equipment adapted for nuclear steam-generators F22B37/006}; manipulators specially adapted for, or associated with, nuclear reactors G21C; {apparatus used for handling wafers during manufacture or treatment of semiconductor H10P72/50}) - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A robot hand capable of reducing the load moment applied on the wrist of the robot hand in lifting an article includes a base, a first hand arm, and a second hand arm. The first hand arm is mounted on the base, includes a holding part configured to hold the article, and is configured such that the holding part is movable between a first distal position away from the base in a first direction, and a first proximal position close to the base more than the first distal position. The second hand arm is mounted on the base, includes a counter balancer weight, and is configured such that the counter balancer weight is movable between a second distal position away from the base in a second direction opposite to the first direction, and a second proximal position close to the base more than the second distal position. ## Claims ### Claim 1 A method of controlling a robot hand, the robot hand including: a base; a first hand arm mounted on the base to be reciprocable on a first track parallel to a first axis, the first hand arm including a holding part configured to hold an article, and the first hand arm configured to move the holding part between (i) a first distal position away from the base in a first direction and (ii) a first proximal position closer to the base than the first distal position; and a second hand arm mounted on the base to be reciprocable on a second track parallel to the first axis, the second hand arm including a counter balancer weight, and the second hand arm configured to move the counter balancer weight between (a) a second distal position away from the base in a second direction opposite to the first direction and (b) a second proximal position closer to the base than the second distal position, wherein the first track and the second track are separate away from each other in a direction intersecting the first axis, the method comprising: moving the counter balancer weight from the second proximal position to the second distal position by the second hand arm; moving the holding part from the first proximal position to the first distal position by the first hand arm, wherein the holding part is moved from the first proximal position to the first distal position by the first hand arm after the counter balancer weight is moved from the second proximal position to the second distal position by the second hand arm; and holding the article by driving the holding part. ### Claim 2 (depends on 1) The method according to claim 1, further comprising: measuring a weight of the article, after said holding the article; calculating an arrangement position at which the counter balancer weight is to be arranged, based on the measured weight of the article; and moving the counter balancer weight to the arrangement position by the second hand arm. ### Claim 3 A robot system, comprising: a robot hand configured to hold and transport an article, the robot hand comprising: a base; a first hand arm mounted on the base, the first hand arm including a holding part configured to hold the article, and the first hand arm configured to move the holding part between (i) a first distal position away from the base in a first direction, and (ii) a first proximal position closer to the base than the first distal position; a second hand arm mounted on the base, the second hand arm including a counter balancer weight, the second hand arm configured to move the counter balancer weight between (a) a second distal position away from the base in a second direction opposite to the first direction, and (b) a second proximal position closer to the base than the second distal position; a first driving unit configured to drive the holding part to move between the first distal position and the first proximal position; and a second driving unit configured to drive the counter balancer weight to move between the second distal position and the second proximal position; and a controller configured to control the first driving unit and the first driving unit, wherein the controller is configured to control the first driving unit to move the holding part from the first proximal position to the first distal position, after controlling the second driving unit to move the counter balancer weight from the second proximal position to the second distal position. ### Claim 4 (depends on 3) The robot system according to claim 3, wherein each of the first driving unit and the second driving unit includes an air cylinder. ### Claim 5 (depends on 3) The robot system according to claim 3, wherein each of the first driving unit and the second driving unit includes a servo motor. ### Claim 6 (depends on 3) The robot system according to claim 3, wherein one of the first driving unit and the second driving unit includes a servo motor, and the other of the first driving unit and the second driving unit includes an air cylinder. ### Claim 7 (depends on 3) The robot system according to claim 3, further comprising: a robot arm to which the robot hand is mounted. ### Claim 8 (depends on 3) The robot system according to claim 3, further comprising: a load sensor, wherein the load sensor is configured to measure a weight of the article, and the controller is configured to control movement of the counter balancer weight by the second hand arm, based on the weight of the article measured by the load sensor.