Safety latch for a tilting bed

Abstract

This invention provides a highly reliable safety device having a high fail-safe feature, which comprises a sector gear rotatably supported on a support base, a bed section supported on the sector gear and tiltable to a predetermined diagnostic angle anywhere from a horizontal position to a standing position of a patient, an off-normal rotation control means such as a limit switch to detect that the rotation of the sector gear relative to the support base exceeds the range of a limit rotation angle and to control its rotation, a hook member provided in a side surface position of the sector gear corresponding to the limit rotation angle beyond the off-normal rotation angle, a hook holding mechanism journaled in a side surface position of said support base which faces the sector gear, and adapted to engage with the hook member to restrict and prevent any further rotation of the sector gear, and whereby the bed section is positively restricted against any further tilting beyond its limit rotation angle, immediately informing an operator of an off-normal state of the safety device, preventing a possible accident on the bed section and the patient.