Transport device with linear-motor drive

{
  "publication_number": "US9555720B2",
  "country": "US",
  "kind": "B2",
  "title": "Transport device with linear-motor drive",
  "abstract": "The transport device for conveying products has several symmetrically configured, movable carriages having inverted U-shape, each carriage having permanent magnets, also has an endless guide rail for guiding the carriages and a linear-motor drive device to drive the carriages. Each symmetric half of each carriage has three running rollers projecting inwardly from sidepieces of the carriage. The three running rollers of the first half rest on first and second guide surfaces on a first side wall of the guide rail, and the three running rollers of the second half rest on first and second guide surfaces on the second side wall of the guide rail. Each guide surface is arranged at an acute angle to a longitudinal center plane of the transport device, and the two guide surfaces of each side wall are at an angle of 80° to 100° to each other.",
  "claims": [
    "1. A transport device for conveying products comprising: at least one movable carriage for conveying a product; a stationary, endless guide rail for guiding the at least one carriage; and a linear-motor drive device for driving the at least one carriage; wherein the at least one carriage comprises at least two permanent magnets, which interact with the linear-motor drive device; and wherein the at least one carriage further comprises a plurality of running rollers, which rest on first and second guide surfaces of the guide rail arranged on different planes and roll along the first and second guide surfaces when the at least one carriage moves; wherein the at least one carriage comprises first and second halves, mirror-symmetric to a longitudinal center plane of the transport device, each of the first and second halves comprising three running rollers, wherein the three running rollers of the first half of the at least one carriage rest on two first and second guide surfaces on a first side wall of the guide rail, and the three running rollers of the second half of the at least one carriage rest on two other first and second guide surfaces on a second side wall of the guide rail; wherein, during movement of the at least one carriage, the three running rollers of the first half of the at least one carriage roll along the first and second guide surfaces on the first side wall of the guide rail, and the three running rollers of the second half of the at least one carriage roll along the first and second guide surfaces on the second side wall of the guide rail; wherein the first and second guide surfaces of each of the first and second side walls are at an angle of 80° to 100° to each other, wherein the first and second guide surfaces of each of the first and second side walls of the guide rail are spaced apart and face each other; and wherein the at least one carriage comprises a substantially horseshoe-shaped or inverted U-shaped base body having sidepieces, from which sidepieces the running rollers inwardly project; wherein the at least one carriage and the guide rail are symmetric relative to the longitudinal center plane; and wherein the first guide surface and the second guide surface of each of the first and second side walls of the guide rail are arranged at an acute angle to the longitudinal center plane, wherein the acute angle between each of the first and second guide surfaces and the longitudinal center plane is 40° to 50°.",
    "2. The transport device according to claim 1, wherein the three running rollers of each of the first and second halves of the at least one carriage are configured in a tilted triangular arrangement, wherein two running rollers have parallel rotational axes and rest on the first guide surface, and wherein the third running roller has a rotational axis tilted at an angle of 80° to 100° to the rotational axes of the first two running rollers and rests on the second guide surface.",
    "3. The transport device according to claim 1, wherein the two guide surfaces of each of the first and second side walls are at an angle of substantially 90° to each other.",
    "4. The transport device according to claim 3, wherein the acute angle between each of the first and second guide surfaces and the longitudinal center plane is substantially 45°.",
    "5. The transport device according to claim 1, wherein the third running roller of each half of the at least one carriage is arranged precisely in the middle between the two other running rollers relative to the longitudinal direction.",
    "6. The transport device according to claim 1, wherein the at least two permanent magnets are arranged toward an end of the sidepieces on an inside surface of the sidepieces.",
    "7. The transport device according to claim 1 or claim 6, wherein the two first running rollers of each half of the at least one carriage are supported rotatably on the base body of the at least one carriage, and the sidepieces of the base body comprise, in a middle section thereof, a U-shaped recess forming a web, on which the associated third running roller is supported."
  ],
  "description_excerpt": "The present invention relates to a transport device with linear motor drive.\n\nTransport devices of this type have already been known for a long time and offer the advantage that the carriages or conveyor elements moved by the linear motor drive can be moved independently of each other, which results in considerable advantages over conventional mechanical transport devices.\n\nOne of the purposes served by these types of transport devices is to be found in, for example, the loading of packaging machines with products as known from U.S. Pat. No. 6,876,896 B1, for example, or from U.S. Pat. No. 5,225,725. In these cases, movable conveyor elements or carriages, each equipped with permanent magnets, are moved along a stationary, endless guide rail. The carriages are driven by means of stationary coils, arranged next to one another in a row, each of which is supplied individually with current, as a result of which local magnetic fields are created, which in turn generate a flow of force between the coils and the permanent magnets. By supplying current intelligently to the individual coils, a moving magnetic field can be generated, which can move each individual carriage independently of any of the other carriages which may be present. Because the guide rail is configured as a closed, endless circuit, problems occur particularly in the area of the curved sections as a result of the high frictional and inertial forces of the running rollers on the guide rail and as a result of the partly present play between the running rollers and the guide rail.",
  "cpc": [
    "B60L 13/03",
    "B61B 13/00",
    "B61B 13/04",
    "B61C 3/00",
    "B65G 2812/99",
    "B65G 54/02"
  ],
  "ipc": [
    "B60L 13/03",
    "B61B 13/00",
    "B61B 13/04",
    "B61C 3/00",
    "B65G 54/02"
  ],
  "assignees": [
    "Uhlmann Pac Systeme GmbH and Co KG"
  ],
  "inventors": [
    "Thomas Aumann",
    "Joerg Riekenbrauck",
    "Wolfgang Krahl",
    "Roberto Linke"
  ],
  "filing_date": "2014-10-15",
  "publication_date": "2017-01-31",
  "grant_date": "2017-01-31",
  "priority_date": "2012-04-18",
  "application_number": "US-201414515412-A",
  "family_id": "47754457",
  "cited_by_count": 15,
  "citations": [
    "US4867579A",
    "US4884898A",
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    "EP0517684A2",
    "EP0577995A2",
    "US6876896B1",
    "US20040007921A1",
    "EP2042759A2",
    "US20090095192A1",
    "WO2010086060A1",
    "US20120018282A1",
    "DE102010028055A1"
  ]
}