Rotary clamp device

{
  "publication_number": "US2024376921A1",
  "country": "US",
  "kind": "A1",
  "title": "Rotary clamp device",
  "abstract": "Provided is a highly durable, compact rotary clamp device. In a housing body, a large diameter hole and a medium-diameter hole are continuously formed in this order from a lower side in an axial direction. A cylindrical protruding member which is hermetically inserted in the large diameter hole is screwed into the housing body. A key member is inserted between the medium-diameter hole and a cylindrical retainer inserted in the medium-diameter hole. The retainer is positioned relative to the housing body in a circumferential direction by the key member.",
  "claims": [
    "1. A rotary clamp device, comprising: a housing body; a large-diameter hole, a medium-diameter hole and a small-diameter hole formed in the housing body in this order from a tip side to a base side in an axial direction; a cylindrical protruding member hermetically inserted into the large-diameter hole and protruding from the housing body to the tip side in the axial direction; a male threaded portion formed on an outer circumferential wall of the cylindrical protruding member and screwed into a female threaded portion formed on an inner circumferential wall of the medium-diameter hole; a cylindrical retainer inserted into the medium-diameter; a first key groove formed on the inner circumferential wall of the medium-diameter hole in the axial direction; a second key groove formed on an outer circumferential wall of the cylindrical retainer in the axial direction so as to face the first key groove; a key member mounted between the first key groove and the second key groove; a piston hermetically inserted into the small-diameter hole to be movable in the axial direction; a piston rod protruding from the piston toward the tip side in the axial direction and protruding outward from the cylindrical protruding member through a cylindrical hole of the cylindrical retainer and a the cylindrical hole of the cylindrical protruding member; an engaging member protruding radially inward from an inner circumference of the cylindrical retainer; and a spiral groove and a linear groove continuously formed in this order from the base side in the axial direction on an outer circumferential wall of the piston rod, said spiral groove and said linear groove being configured to receive the engaging member during at least a clamping operation of the rotary clamp device; wherein a part of a circumferential wall of the first key groove is formed so as to be radially outward of an inner circumference of the large-diameter hole. 2. A rotary clamp device, comprising: a housing body; a large-diameter hole, a medium-diameter hole and a small-diameter hole formed in the housing body in this order from a tip side to a base side in an axial direction; a cylindrical protruding member hermetically inserted into the large-diameter hole and protruding from the housing body to the tip side in the axial direction; a male threaded portion formed on an outer circumferential wall of the cylindrical protruding member and screwed into a female threaded portion formed on an inner circumferential wall of the medium-diameter hole; a cylindrical retainer inserted into the medium-diameter; a first key groove formed on the inner circumferential wall of the medium-diameter hole in the axial direction; a second key groove formed on an outer circumferential wall of the cylindrical retainer in the axial direction so as to face the first key groove; a key member mounted between the first key groove and the second key groove; a piston hermetically inserted into the small-diameter hole to be movable in the axial direction; a piston rod protruding from the piston toward the tip side in the axial direction and protruding outward from the cylindrical protruding member through a cylindrical hole of the cylindrical retainer and a cylindrical hole of the cylindrical protruding member; an engaging member; and a spiral groove and a linear groove continuously formed in this order from the base side in the axial direction, said spiral groove and said linear groove being configured to receive the engaging member during at least a clamping operation of the rotary clamp device; wherein a part of a circumferential wall of the first key groove is formed so as to be radially outward of an inner circumference of the large-diameter hole. 3. The rotary clamp device of claim 2, wherein the spiral groove and linear groove are formed on one of the piston rod and the cylindrical retainer."
  ],
  "description_excerpt": "The present invention relates to a rotary clamp device for fixing objects to be fixed, such as workpieces, molds, tools, etc., to a table, a robot arm, etc. by rotating and lowering a clamp arm.\n\nA conventional rotary clamp device of this type is described in Patent Document 1 (Japan. Unexamined Utility Model Application Publication No. 5-52304). The conventional technology consists of the following.\n\nIn the rotary clamp device shown in FIG. 5 of Patent Document 1. a piston is inserted into a cylindrical hole of a cylinder tube. A cylindrical rod cover is inserted into the tip of the cylindrical hole of the cylinder tube to protrude upward from the cylinder tube. A piston rod. which protrudes from the piston toward the tip side, is inserted into the cylindrical hole of the rod cover to protrude to the outside of the cylinder cover. The rod cover is received from below by a stepped portion formed on the inner circumferential wall of the cylindrical hole of the cylinder tube, and is prevented from coming off from the cylindrical hole of the cylinder tube by a retaining ring. A threaded hole is penetrated radially through the cylindrical wall of the cylinder tube, and a screw is screwed into the threaded hole. The tip of the screw is inserted into a recess formed on the outer circumferential wall of the rod cover. According to this, the rod cover is prevented from rotating with respect to the cylinder tube.\n\nIn addition, in the rotary clamp device of FIG. 1 of Patent Document 1. the rod cover is fixed to the cylinder tube by a ring nut instead of the above retaining ring.",
  "cpc": [
    "F16B 7/182",
    "B23Q 3/06",
    "B25B 5/04",
    "B25B 5/062",
    "F15B 15/06",
    "F15B 15/068",
    "F15B 15/14",
    "F15B 15/1433",
    "F15B 15/1438"
  ],
  "ipc": [
    "B23Q 3/06",
    "B25B 5/04",
    "F15B 15/14",
    "F16B 7/18"
  ],
  "assignees": [
    "Kosmek KK"
  ],
  "inventors": [
    "Masahiro Yoshimi"
  ],
  "filing_date": "2022-09-12",
  "publication_date": "2024-11-14",
  "priority_date": "2021-10-18",
  "application_number": "US-202218692803-A",
  "family_id": "86059061",
  "cited_by_count": 0,
  "citations": [
    "US4508327A",
    "US5820118A",
    "US6663093B2",
    "US6902158B2",
    "US20030189279A1",
    "US7574953B2",
    "US9032862B2"
  ]
}