Chain with a single direction of curvature and application to a handrail

{
  "publication_number": "US4267922A",
  "country": "US",
  "kind": "A",
  "title": "Chain with a single direction of curvature and application to a handrail",
  "abstract": "The chain has a single direction of curvature and is capable of passing over pinions of small diameter. This chain is made up of a classic chain comprising at regular intervals a link to which is fixed a block having at least two rectilinear coplanar faces and tangent to the pins of the links and each extending over a length equal to the interval respectively from one part to the other of the link. An application of this chain consists in a variable speed handrail.",
  "claims": [
    "1. A chain with a single direction of curvature comprising a classic chain of single links and second links in regular succession and a block fixed to each of said second links having a plane face tangent to the axes of said second links extending on either side of said second links in the longitudinal direction of the chain over a length at least equal to the total length of said single links adjacent said second links, adjacent ones of said blocks overlapping along the chain.",
    "2. A chain as described in claim 1 characterized by the fact that said face has three parts, a central part and two lateral parts, the central part of a block coming into position between the two lateral parts of a contiguous block.",
    "3. A chain in accordance with either of claims 1 or 2 characterized by the fact that each of the said blocks comprises further an adjusting system coming into bearing against the contiguous block.",
    "4. A chain in accordance with claim 3 characterized by the fact that the adjustment system consists of a screw having a head bearing against a face of the contiguous block perpendicular to said face tangent to the axes.",
    "5. A chain forming a handrail for a variable speed transporter constituted by individual handgrips connected by a deformable link having a constant perimeter characterized by the fact that the link is a chain having a single direction of curvature in accordance with any of claims 1 to 4.",
    "6. A chain in accordance with claim 5 characterized by the fact that said blocks each have a cover providing continuity of the exterior surface."
  ],
  "description_excerpt": "The present invention relates to a chain with a single direction of curvature, that is, in which each link can pass freely only on one side with respect to the line of the axes of the divisor axles of adjacent links; thus, it can pass around two pinions while being practically without flexure between them under the action of a force tending to apply against them. Chains with a single direction of curvature are known; they are used primarily as conveyors for merchandise. One known construction for such chains is described in French Pat. No. 1,297,285. A similar construction is described in French Pat. No. 2,207,069 (U.S. Pat. No. 3,884,152). This type of chain is perfectly adapted to certain uses, primarily for handling units. On the other hand, they have the inconvenience of not being suitable for small values of pitch, thus for pinions of small diameter, because each link must be small and the requirements of dimensional precision and of strength lead to a prohibitive cost in view of the large number of links therefore necessary.\n\nAnother type of chain with a single direction of curvature is described in French Patent Application No. 7420681. The chain has a single direction of curvature and is constituted by a normal chain mounted with blocks which prevent all possibility of bending in the half plane where they are located. But such a chain does not absorb shearing forces, thus the play and the elastic elongation of the links lead to a flexing in the moving portions of the length of chain supported between two pinions.",
  "cpc": [
    "F16G 13/20",
    "B65G 17/08",
    "B65G 2201/02"
  ],
  "ipc": [
    "B65G 17/00",
    "B65G 17/08",
    "B65G 17/38",
    "B65G 23/00",
    "F16G 13/18"
  ],
  "assignees": [
    "REGIE AUTONOME TRANSPORTS"
  ],
  "inventors": [
    "PATIN PIERRE",
    "PLAGNE JEAN"
  ],
  "filing_date": "1979-06-28",
  "publication_date": "1981-05-19",
  "grant_date": "1981-05-19",
  "priority_date": "1978-07-11",
  "application_number": "US-5279279-A",
  "family_id": "9210569",
  "citations": [
    "DE1171813B",
    "DE499428C",
    "US323621A",
    "US3884152A"
  ]
}