# US 12,179,338 B2 · Parallel gripper with adaptive clamping surfaces > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,179,338 B2 - Document ID: US12179338B2 - Status: Granted - Kind: B2 - Application number: 17/465,274 - Filed: 2021-09-02 - Published: 2022-06-09 - Granted: 2024-12-31 - Earliest claimed: 2020-12-03 - Assignees: Tecan Trading AG - Applicants: Tecan Trading AG - Inventors: Mirco Brennwald; André Häfelfinger; Marcel Aschwanden - Web page: https://patentgrep.com/patent/US12179338B2 ## CPC - B25J 15/0028: {with movable, e.g. pivoting gripping jaw surfaces} - B25J 15/0253: {comprising parallel grippers} - B25J 15/0042: {V-shaped gripping surfaces} - B25J 15/12: with flexible finger members - 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}) ## Abstract Arrangements of a gripper finger and a clamp for use in an automated parallel gripper are provided. The arrangements will include first and second gripper fingers that are moveable in a direction of translation (y), whereby the clamp is connected to the gripper finger at an underside thereof, so as to be rotational about a vertical axis of rotation. The clamp has a front face with a contact surface for engagement with a lateral edge of an item to be gripped and has a default orientation in which the front face is parallel to a lateral direction (x) that is perpendicular to the direction of translation (y) and to the vertical rotation axis. The arrangements are additionally provided with a self-alignment feature which includes first and second biasing mechanisms arranged at either side of the rotation axis in lateral direction (x). Each biasing mechanism has a first part connected to the finger and a second part connected to the clamp and is configured to exert a centering force that urges the first and second parts of each biasing mechanism into alignment with each other. When the clamp is in the default orientation, each biasing mechanism is preloaded to exert an equal moment load on the clamp in the direction of translation (y). ## Claims ### Claim 1 An arrangement of a gripper finger and a clamp for use in an automated parallel gripper comprising: first and second gripper fingers that are moveable towards each other and away from each other in a direction of translation (y), wherein the gripper finger extends in a vertical direction (z) perpendicular to the direction of translation (y) and the clamp is connected to the gripper finger at an underside thereof so as to be rotational about a vertical axis of rotation parallel to the vertical direction (z), and wherein the clamp has a front face with a contact surface for engagement with a lateral edge of an item to be gripped, the clamp having a default orientation in which the front face is parallel to a lateral direction (x) that is perpendicular to the direction of translation (y) and to the vertical axis of rotation that is parallel to the vertical direction (z), and wherein the arrangement further comprises a self-alignment mechanism which comprises first and second biasing mechanisms arranged at either side of the rotation axis in the lateral direction (x) which urges the clamp to adopt the default orientation in an unloaded condition of the clamp, wherein: (i) each biasing mechanism has a first part connected to the finger and a second part connected to the clamp and is configured to exert a centering force that urges the first and second parts of each biasing mechanism into alignment with each other; and (ii) when the clamp is in the default orientation, each biasing mechanism is preloaded to exert an equal moment load on the clamp in the direction of translation. ### Claim 2 (depends on 1) The arrangement of claim 1, wherein the first part of each biasing mechanism has a centre axis; the second part of each biasing mechanism has a centre axis; and in the default orientation, the centre axis of the first and second parts of each biasing mechanism are slightly offset from each other in the direction of translation (y), so as to generate the preload. ### Claim 3 (depends on 1) The arrangement of claim 1, wherein the first part of each biasing mechanism is retained in a corresponding mounting recess in the gripper finger; the second part is retained in a corresponding mounting recess in the clamp, wherein corresponding recesses in the finger and the clamp face each other in the vertical direction (z); and in the default orientation of the clamp, a centre axis of each mounting recess in the finger is offset in the direction of translation (y) from a centre axis of the corresponding recess in the clamp. ### Claim 4 (depends on 3) The arrangement according to claim 3, wherein the first and second biasing mechanisms are respectively formed by first and second coil springs arranged in generally vertical direction, and wherein the first part of each biasing mechanism is formed by an upper section of the corresponding coil spring, which is retained in the corresponding mounting recess in the gripper finger; the second part of each biasing mechanism is formed by a lower section of the corresponding coil spring, which is retained in the corresponding mounting recess in the clamp; and in the default orientation of the clamp, a centre axis of each upper section of the coil spring is offset from a centre axis of the corresponding lower section. ### Claim 5 (depends on 1) The arrangement of claim 1, further comprising at least one anti-rotation pin that is fixed to the clamp and extends into an opening in the gripper finger, wherein the opening has a larger diameter than a diameter of the at least one anti-rotation pin. ### Claim 6 (depends on 5) The arrangement according to claim 5, comprising first and second anti-rotation pins arranged at either side of the vertical rotation axis in the lateral direction (x), wherein: the first and second anti-rotation pins respectively form the second part of each biasing mechanism; the first part of each biasing mechanism is formed by a resilient O-ring that is retained in the corresponding mounting recess in the gripper finger, wherein the mounting recess forms part of the opening in the gripper finger through which the respective anti-rotation pin extends; and in the default orientation, the centre axis of each pin is offset from the centre axis of the corresponding O-ring, such that each O-ring is pre-compressed between the mounting recess and one side of the corresponding pin in the direction of translation (y). ### Claim 7 (depends on 1) The arrangement according to claim 1, wherein each biasing mechanism comprises a set of first and second magnets arranged opposite from each other in vertical direction, and wherein the first magnet of each set is fixed to the gripper finger; the second magnet of each set is fixed to the clamp; and in the default orientation, a centre axis of the magnetic field generated by each first magnet is offset in the direction of translation (y) from a centre axis of the magnetic field generated by each corresponding second magnet. ### Claim 8 (depends on 7) The arrangement according to claim 7, wherein the first and second magnets in each biasing mechanism are arranged so as to have attracting polarities or are arranged to as to have repelling polarities. ### Claim 9 (depends on 1) The arrangement according to claim 1, wherein each biasing mechanism is formed by a flexible element that permits elastic deformation via torsion and bending; a first part of each flexible element is attached to an external, planar surface of the gripper finger, wherein the planar surface faces in the direction of translation (y); a second part of each flexible element is attached to an external, planar surface of the clamp that faces in the same direction of translation (y); and the planar surface of the clamp is offset from the corresponding planar surface of the gripper finger in the direction of translation (y) such that the second part of each flexible element is elastically deformed relative to the corresponding first part, so as to generate the preload in the default orientation. ### Claim 10 (depends on 1) The arrangement according to claim 1, wherein the front face of the clamp is provided with at least one contact pad having a contact surface with a high coefficient of friction. ### Claim 11 (depends on 10) The arrangement according to claim 10, wherein the front face is provided with first and second contact pads which are spaced in the lateral direction (x). ### Claim 12 (depends on 1) The arrangement according to claim 1, wherein the front face of the clamp comprises a shaped recess having a first set of opposed conical surfaces that taper towards a base of the recess in the vertical direction (z) and a second set of opposed conical surfaces that taper towards the base in the lateral direction (x). ### Claim 13 (depends on 1) An automated parallel gripper comprising first and second gripper fingers provided with the arrangement of the gripper finger and clamp according to claim 1.