A patient support apparatus includes a base, a seat supported by the base and a backrest pivotable between an upright position and a reclined position. In one embodiment, a backrest support member is coupled to the backrest and is adapted to move between a stowed position in which the backrest support member does not support the backrest and a deployed position in which the backrest support member does support the backrest. Movement to the deployed position occurs in response to activation of an emergency control. In other embodiments, the base includes a portion that moves into an extended position underneath the backrest when the backrest is in the reclined position. Movement of the base portion to the extended position also occurs in response to activation of an emergency control.

A patient support apparatus includes a base, a seat supported by the base and a backrest pivotable between an upright position and a reclined position. In one embodiment, a backrest support member is coupled to the backrest and is adapted to move between a stowed position in which the backrest support member does not support the backrest and a deployed position in which the backrest support member does support the backrest. Movement to the deployed position occurs in response to activation of an emergency control. In other embodiments, the base includes a portion that moves into an extended position underneath the backrest when the backrest is in the reclined position. Movement of the base portion to the extended position also occurs in response to activation of an emergency control.

A patient support apparatus includes a frame, a stationary member mounted relative to the frame, a movable member having a pivot member rotatably mounting the movable member about the stationary member, and a fastener securing the pivot member to the stationary member. The patient support apparatus also includes a joint between the pivot member and the stationary member, which is configured to apply a tension force on the fastener.

A patient support apparatus includes a frame, a stationary member mounted relative to the frame, a movable member having a pivot member rotatably mounting the movable member about the stationary member, and a fastener securing the pivot member to the stationary member. The patient support apparatus also includes a joint between the pivot member and the stationary member, which is configured to apply a tension force on the fastener.

A dental includes a chair module, a lift module, and a base module, the base module configured to releasably attach to and integrate with the lift module, the lift module configured to releasably attach to and integrate with the chair module.

A dental includes a chair module, a lift module, and a base module, the base module configured to releasably attach to and integrate with the lift module, the lift module configured to releasably attach to and integrate with the chair module.

A patient positioning apparatus for an X-ray dental imaging system includes a head rest and a chair separate from and spaced from the head rest. The chair has a seat portion and a back rest coupled to the seat portion. The chair further includes a locking system that locks a position of the back rest relative to the seat portion.

A patient positioning apparatus for an X-ray dental imaging system includes a head rest and a chair separate from and spaced from the head rest. The chair has a seat portion and a back rest coupled to the seat portion. The chair further includes a locking system that locks a position of the back rest relative to the seat portion.

A seat positioning system includes a base frame having a pair of forward slots and a pair of rear slots, and a seat frame having a front end and a back end. The seat frame is coupled to the base frame and movable relative to the base frame. A first pair of linkages is slideably coupled to the pair of forward slots and connects the frames. A first pair of locking devices has a locked configuration adapted to prevent the first pair of linkages from sliding relative to the pair of forward slots and an unlocked configuration adapted to allow the first pair of linkages to slide relative to the pair of forward slots. A second pair of linkages slideably is coupled to the pair of rear slots and connects the frames. An actuator is pivotally connected to both the seat frame and the base frame and is configured to extend and contract to move the seat frame relative to the base frame.

A seat positioning system includes a base frame having a pair of forward slots and a pair of rear slots, and a seat frame having a front end and a back end. The seat frame is coupled to the base frame and movable relative to the base frame. A first pair of linkages is slideably coupled to the pair of forward slots and connects the frames. A first pair of locking devices has a locked configuration adapted to prevent the first pair of linkages from sliding relative to the pair of forward slots and an unlocked configuration adapted to allow the first pair of linkages to slide relative to the pair of forward slots. A second pair of linkages slideably is coupled to the pair of rear slots and connects the frames. An actuator is pivotally connected to both the seat frame and the base frame and is configured to extend and contract to move the seat frame relative to the base frame.