Patent ID: 8814238

Claim:
A clamping apparatus comprising: a frame having an opening through which an imaginary solid having a rectangular shape as viewed in plan with dimensions of at least 24×24 inches as viewed in plan can extend vertically from below the frame to at least 12 inches above the frame without any portion of the apparatus extending into the imaginary solid, the frame extending around an entire outer periphery of the imaginary solid as viewed in plan; first and second opposing clamping arms pivotably mounted on the frame for pivoting with respect to the frame about parallel horizontal, axes towards and away from each other to grasp and release a load, each of the clamping arms having a contact portion for contacting the load, the clamping arms being pivotable to bring the contact portions of both of the clamping arms into coincidence with opposite surfaces of the imaginary solid at the same time, each of the clamping arms comprising a 4-bar linkage including a lever portion having an upper end pivotably supported by the frame for pivoting with respect to the frame about a first horizontal axis and a lower end pivotably connected to the contact portion for pivoting with respect to the contact portion about a second axis parallel to the first axis, and a control rod having a lower end pivotably connected to the contact portion for pivoting with respect to the contact portion about a third axis parallel to the first axis and an upper end pivotably supported by the frame for pivoting with respect to the frame about a fourth axis parallel to the first axis; and at least one actuator connected to the clamping arms for moving the clamping arms towards and away from each other.