{
  "$type": "site.standard.document",
  "description": "The invention relates to a four-wheel drive system and an electric drive system for a four-wheel drive vehicle which improve running performance of an automotive vehicle by inhibiting a driving torque from becoming insufficient upon occurrence of a slip. A R slip sensing means (137) of a…",
  "path": "/patents/1076246",
  "publishedAt": "2005-06-29T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "B60K6/52",
    "HITACHI LTD [JP]"
  ],
  "textContent": "The invention relates to a four-wheel drive system and an electric drive system for a four-wheel drive vehicle which improve running performance of an automotive vehicle by inhibiting a driving torque from becoming insufficient upon occurrence of a slip. A R slip sensing means (137) of a DC-motor-torque calculating means (139) senses a slip due to a spin of rear wheels (15R, 15L). When the rear wheel slip is sensed, an R slip DC-motor-torque correcting means (139) corrects a torque of the rear wheels (15R, 15L) so that a driving force of the rear wheels (15R, 15L) is reduced and then increased. The R slip DC-motor-torque correcting means (139) reduces a driving torque of the rear wheels (15R, 15L) to eliminate the slip and holds the reduced driving torque until the slip is eliminated, and then increases the driving torque to a value lower than a value which the driving torque has taken at the time of occurrence of the slip. The driving torque is increased to a predetermined limit value depending on the number of slips.",
  "title": "Four-wheel drive system"
}