| 主权项 |
1. A device for compressing the chest of a patient, where said patient is characterized by a chest and a sternum defining an area of said sternum, said device comprising:
a compression pad adapted to contact the chest of the patient in the area of the patient's sternum, and limited to the area of the patient's sternum; a drive system operable to exert force on the compression pad to impart repeated cycles of compression and release of compression on the chest of the patient; wherein the drive system comprises a cam system operable to force the compression pad downward, and the cam system comprises a radial cam, and the radial cam comprises a cam plate and a cam shaft, said cam shaft being operable to rotate the cam plate and said radial cam is operably connected to the compression pad through a follower; and wherein the cam plate is operable to rotate through a first portion of rotation, a second portion of rotation and a third portion of rotation, and said cam is shaped such that, for the first portion of rotation, the cam follower is translated in a first direction at a uniform compression rate to provide a compression to the patient at uniform rate, for the second portion of rotation comprising 90° to 180° of rotation of the cam plate, the cam follower is held substantially stationary to provide a static period of compression by a shape of the cam plate in the second portion comprising an isodiametric top radius where a radius of a contact point with the follower is a substantially fixed radius relative to the cam shaft, in which the compression component is held at a substantially constant threshold of compression, for the third portion of rotation, the follower is translated in a second direction at a rate substantially greater than the uniform compression rate, such that the compression pad is released from downward tension upon the chest of the patient. |
