Force sensor

{
  "publication_number": "US12092539B2",
  "country": "US",
  "kind": "B2",
  "title": "Force sensor",
  "abstract": "An elastic body is fixed to a main body and a movable body and is deformable according to the movement of the movable body. A strain sensor is provided on the elastic body and includes a strain body. The movable body includes an opening. The stopper member includes a first contact portion and a second contact portion provided inside the opening, whose distances from the opening are different from each other. The first contact portion is located in a direction in which the movable range of the strain body is great, and the second contact portion is located in a direction in which the movable range of the strain body is small.",
  "claims": [
    "1. A force sensor comprising: a main body; a movable body movable with respect to the main body; an elastic body fixed to the main body and the movable body and deformable according to movement of the movable body; a strain sensor provided on the elastic body and including a strain body; an opening formed in the movable body; a stopper member provided inside the opening, including a first contact portion and a second contact portion distances of which from the opening are different from each other; and a fixing member fixing the stopper member to the main body, the opening is circular, the stopper member is cylindrical, and the first contact portion is an outer surface of the stopper member corresponding to a first direction, and the second contact portion is two projections provided on the outer surface of the stopper member corresponding to a second direction, wherein the movable range of the strain body is greater in the first direction than the second direction.",
    "2. The force sensor of claim 1, wherein a distance between the first contact portion and an inner surface of the opening is a first distance, a distance between the second contact portion and an inner surface of the opening is a second distance, and the second distance is less than the first distance.",
    "3. The force sensor of claim 1, wherein the stopper member comprises a first portion and a second portion having a diameter less than a diameter of the first portion, and the projection is provided on the second portion.",
    "4. The force sensor of claim 3, wherein the stopper member comprises a third portion provided on the second portion and having a diameter less than the diameter of the second portion.",
    "5. The force sensor of claim 4, wherein a distance between a side surface of the third portion of the stopper member and the inner surface corresponding to the third portion of the opening is greater than the first distance.",
    "6. The force sensor of claim 5, wherein the third portion comprises a first slit, and the movable body comprises a second slit communicating to the opening and corresponding to the first slit.",
    "7. The force sensor of claim 6, further comprising: a jig inserted between the side surface of the third portion of the stopper member and the inner surface corresponding to the third portion of the opening.",
    "8. The force sensor of claim 7, wherein the jig comprises a key integrally inserted to the first slit and the second slit."
  ],
  "description_excerpt": "Embodiments of the present disclosure relate to an elastic body used for, for example, robot arms and the like, and a force sensor using the same.\n\nForce sensors are used, for example, by robot arms and the like, and they detect a force (Fx, Fy, Fz) and a moment (Mx, My, Mz) with respect to three axes (x, y and z) orthogonal to each other. The force sensors comprise a stopper to prevent the strain sensor from being destroyed by excessive force or moment (see, for example, JP 2018-48915 A).\n\nThe stopper includes, for example, a cylindrical stopper member and the stopper member is provided within a circular opening provided in a movable body of the force sensor. A slight gap is provided between the outer surface of the stopper member and the inner surface of the opening.\n\nInside the force sensor, an elastic body fixed to the main body and the movable body is provided and, for example, a strain body which constitutes a strain sensor is provided on the elastic body (hereinafter, the elastic body and the strain body are referred to together as the sensor body). When the rigidity of the sensor body is different in each axial direction, it is difficult to protect the strain sensor for all directions with a stopper consisting of a cylindrical stopper member and a circular opening.\n\nEmbodiments of the present disclosure provide a force sensor including a stopper which can reliably protect the strain sensor.",
  "cpc": [
    "G01L 1/26",
    "B25J 19/02",
    "G01L 1/22",
    "G01L 1/2206",
    "G01L 5/161",
    "G01L 5/1627"
  ],
  "ipc": [
    "G01L 1/22",
    "G01L 1/26",
    "G01L 5/161"
  ],
  "assignees": [
    "Nidec Copal Electronics Corp"
  ],
  "inventors": [
    "Takayuki Endo",
    "Yoko YASUTOMI"
  ],
  "filing_date": "2021-06-29",
  "publication_date": "2024-09-17",
  "grant_date": "2024-09-17",
  "priority_date": "2019-01-28",
  "application_number": "US-202117361984-A",
  "family_id": "71840438",
  "cited_by_count": 0,
  "citations": [
    "JPS6435331A",
    "US5945606A",
    "CN201277893Y",
    "US9481089B2",
    "US10647007B2",
    "JP2018048915A",
    "US10527509B2",
    "US20180252604A1",
    "US20190391023A1",
    "WO2018163580A1",
    "US10654173B2",
    "US10589431B2",
    "CN208206368U"
  ]
}