| 摘要 |
Load transferring apparatus comprises a base member, a planar platform for supporting a load and a drive arm pivotally mounted on the base member for moving the platform in plane between a retracted position at which the platform assumes a first orientation and an extended position at which the platform assumes a second angularly transposed orientation while remaining substantially in the plane occupied when in the retracted position. The drive arm is fixed to a drive arm shaft which, in turn, is rotatably mounted on the base member. A constraining link extends between the base member and the platform and is generally parallel to the drive arm. An elevator drive is operable for moving the base member raised and lowered positions and a coupling drivingly connects the drive arm shaft to the drive shaft throughout a range of positions between the raised position and the lowered position. The base plate includes an upstanding stop plate. A tension spring extends between the platform and the drive arm to bias the drive arm into a proximate relationship with the stop plate and to bias the platform to the retracted position. A pair of juxtaposed magnets of opposite polarity are respectively mounted on the drive arm and on the stop plate to thereby draw the drive arm toward the stop plate. The apparatus of the invention may be used in combination with a load lock defining a chamber having a substantially particle free environment.
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