US Patent 7392554 Powered patient lift device

A powered patient lift device includes a main frame having a beam and a wheel chassis. The top of the beam is pivotally connected with a lifting arm. One end of the lifting arm is provided with a seat. A power unit is adapted to drive a lifting unit which then links the lifting arm to move. A control unit is to activate the power unit. A knee support is disposed at a lower section of the beam. The knee support is provided with a knee pad to engage with a user's knee. When the lifting unit is activated, the lifting arm is linked to move the supporting unit to assist the user to stand up or to sit down.